A spokesman for Avon & Wiltshire Mental Health Partnership NHS Trust, said: "At the point [early 2015] he made a specific threat against a named individual, our staff took immediate and appropriate action to inform the police.
"Criminal justice procedures were subsequently instigated and he was formally discharged from our services.”
Langdell, 26, from Cheshunt, Hertfordshire was sentenced at St Albans CRown Court this morning.
England Women prepare to come to Wycombe
Luke Ashmead
BBC Three Counties Radio sport
The England's men's team have played their final warm up match for the Euro 2016... but tomorrow all eyes will be on the Lionesses.
All the information on how to get there and to watch the game is on the Wycombe Wanderes website, but if you can't get there you can watch it on BBC Two from 17:00.
CC Smugglers set to 'Take It To The Bridge' for BBC Music Day
Alex Pope
BBC Local Live
Anyone who can make it to Bedford tonight is being asked to "Take It To The Bridge".
A special performance by CC Smugglers will take place at the town's Suspension Bridge on The Embankment from 18:30.
It's your chance to see a BBC Introducing band who will be supporting The Boss, Bruce Springsteen on his upcoming tour.
The whole event is all part of the second annual BBC Music Day.
Thomas Nugent/GeographCopyright: Thomas Nugent/Geograph
Police constable dismissed after misconduct hearing into paralysed moped rider
Andrew Woodger
BBC News
One officer has lost his job, while another has been issued with a warning at the end of a police misconduct hearing.
The hearing was told the officers seemed more interested in making an arrest than helping a boy who had come off his moped following an incident where he was riding it on a footpath in Hemel Hempstead.
PC Stuart Francis has been instantly dismissed after being found guilty of gross misconduct.
PC Rishi Patel was found guilty of misconduct and received a written warning from Hertfordshire Police.
War time computer re-enactments take place at Bletchley Park
Nick Higham
BBC Correspondent
How do you crack Hitler's most secret cipher?
For the first time ever, all the equipment used in making and breaking the German Lorenz cipher has been demonstrated and re-enacted at The National Museum of Computing at Bletchley Park.
The demos included encrypting and decrypting messages using original and reconstructed equipment in the presence of re-enactment Wrens and cryptanalysts.
TNMOCCopyright: TNMOC
Among them was Irene Dixon (pictured below), one of the very first Colossus Wren operators.
I had the great pleasure of interviewing her and she told me they realised they were working in codes, but didn't know they were working on "Hitler codes".
TNMOCCopyright: TNMOC
More from the police misconduct hearing
PCs Francis and Patel denied using excessive force on the injured boy and of providing dishonest or misleading accounts of what happened.
One witness, Lisa Sandridge, told the hearing: "His [PC Francis's] behaviour was terrible. He didn't show any concern.
He gave him no first aid. "PC Rishi Patel was kneeling on Christian-Lee's legs as he was worried he was going to be kicked in the face. "Christian-Lee was in no state to be kicking anyone in the face."
The hearing in Hatfield is yet to decide what action will be taken against the two officers.
Misconduct hearing finds police officers guilty
Nicola Haseler
BBC Three Counties
Christian-Lee Thompson, now aged 16, was left paralysed and with brain damage after the incident on a disused railway line in Hemel Hempstead in July of last year.
He didn't have a helmet on at the time and was riding in an area only meant for walkers and cyclists.
ContributedCopyright: Contributed
The officer denied trying to arrest him using unnecessary force and providing misleading accounts of what happened.
PC Stuart Francis was found guilty of gross misconduct and PC Rishi Patel of misconduct.
Police officers guilty of misconduct for using force on injured teenager
PC Stuart Francis was found guilty of gross misconduct at a police disciplinary hearing over the way he dealt with 15-year-old Christian-Lee Thompson.
PC Rishi Patel was found guilty of misconduct.
BreakingHertfordshire police officers found guilty at misconduct hearing
Two Hertfordshire police officers have been found guilty at a misconduct hearing today.
It comes after a boy left paralysed after being knocked off his moped was held to the ground by police.
More to follow.
Residents 'furious' after human waste left behind after travellers leave
Matt Lockwood
BBC Three Counties Radio
I've been talking to a very angry Richard Roberts, who lives in Dunstable close to where a group of travellers have left tonnes of rubbish behind after leaving a site in the town.
He says there's human excrement on the nearby cycleway, adding if he did a quarter of the damage left he'd be "arrested".
He told me the matter has been going on for months and the council needs to "find them a plot of land" and "sort it out."
BBCCopyright: BBC
Clean up operations at Dunstable travellers' site expected to take several hours
Matt Lockwood
BBC Three Counties Radio
Council workers are currently cleaning up a high amount of rubbish left behind by travellers in Dunstable.
The team from Biffa waste management are expected to be finished this afternoon.
The mess was left after a number of caravans left the site last night.
Lee ArmstrongCopyright: Lee Armstrong
Lee ArmstrongCopyright: Lee Armstrong
Travellers leave tonnes of rubbish behind in Dunstable
Matt Lockwood
BBC Three Counties Radio
More than 1.5 tonnes (1500kg) of rubbish have been left behind by a group of travellers in Dunstable.
I've seen the waste, which includes human excrement, and was left at a skatepark behind the Grove Theatre in the town.
BBCCopyright: BBC
There's also tyre damage on surrounding fields.
BBCCopyright: BBC
Fire in disused building at Bletchley Park
Alex Pope
BBC Local Live
There's been a fire in an unoccupied building at Bletchley Park.
It's been confirmed to us that it wasn't one of the buildings on the heritage site, but was a derelict building dating from 1943. It was an extension of Block D.
Crews from Bletchley, Great Holm, Newport Pagnell and Winslow attended.
When the England team came to Aylesbury
BBC Sport
Twenty-eight years ago a bit of history was made in Aylesbury...
The England team came to Buckingham Road to complete their preparations for Euro '88.
Live Reporting
Alex Pope
All times stated are UK
Get involved
- A man who killed a teacher and then sexually assaulted her corpse has been given a life sentence
- The sister of a mother-of-four killed in her home has appeared in court accused of her murder
- Two police officers have been found guilty of misconduct over their treatment a 15-year-old boy left paralysed when he came off a moped
Video caption: Bletchley Park: How Hitler's Lorenz cipher was brokenBletchley Park: How Hitler's Lorenz cipher was broken 
BBC WeatherCopyright: BBC Weather 
Getty ImagesCopyright: Getty Images 
Getty ImagesCopyright: Getty Images 
Thomas Nugent/GeographCopyright: Thomas Nugent/Geograph 
TNMOCCopyright: TNMOC 
TNMOCCopyright: TNMOC 
ContributedCopyright: Contributed 
BBCCopyright: BBC 
BBCCopyright: BBC 
Lee ArmstrongCopyright: Lee Armstrong 
Lee ArmstrongCopyright: Lee Armstrong 
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BBCCopyright: BBC 
Video caption: BBC Rewind - England v Aylesbury Euro '88BBC Rewind - England v Aylesbury Euro '88
Latest PostOur live coverage across the day
Andrew Woodger
BBC News
That's all from the Local Live team today.
Friday's headlines have included:
We'll be back with you on Monday from 08:00
Bletchley Park: How Hitler's Lorenz cipher was broken
Equipment used to break the German Lorenz cipher was demonstrated at the Bletchley Park based National Museum of Computing today.
This is how it all worked...
Video content
Weather: Mist could bring drizzle later
BBC Weather
There is a chance of patchy drizzle this evening as the temperature dips to 10C (50F).
Overnight mist will clear as we work through Saturday morning to leave sunshine, but a risk of heavy showers as it peaks at 22C (72F).
For more detail, visit BBC Weather.
Carl Langdell sentencing: Mental health trust alerted police about killer
Andrew Woodger
BBC News
The mental health trust which dealt with killer Carl Langdell says it reported his earlier threats to police.
Langdell has been jailed for a minimum of 26 years for killing Katie Locke, 23, in Hertfordshire on Christmas Eve.
A spokesman for Avon & Wiltshire Mental Health Partnership NHS Trust, said: "At the point [early 2015] he made a specific threat against a named individual, our staff took immediate and appropriate action to inform the police.
"Criminal justice procedures were subsequently instigated and he was formally discharged from our services.”
Langdell, 26, from Cheshunt, Hertfordshire was sentenced at St Albans CRown Court this morning.
England Women prepare to come to Wycombe
Luke Ashmead
BBC Three Counties Radio sport
The England's men's team have played their final warm up match for the Euro 2016... but tomorrow all eyes will be on the Lionesses.
The UEFA Women’s 2017 European Championship qualifier will be held at Adams Park in High Wycombe.
The game, against Serbia, kicks off at 17:30.
All the information on how to get there and to watch the game is on the Wycombe Wanderes website, but if you can't get there you can watch it on BBC Two from 17:00.
Watford release defender Ekstrand
Watford defender Joel Ekstrand is to leave at the end of his contract after four years at Vicarage Road.
Read morePoulter injury means he's unlikely to feature in Ryder Cup
Geoff Doyle
BBC Three Counties Radio sport
Woburn's Ian Poulter will miss the next four months of the season with a foot injury.
The Ryder Cup is at the end of September and start of October, so he’s almost certain to miss out.
'Depraved' first date killer jailed
A man who murdered a teacher on their first date before sexually assaulting and taking pictures of her corpse is jailed for life.
Read moreCC Smugglers set to 'Take It To The Bridge' for BBC Music Day
Alex Pope
BBC Local Live
Anyone who can make it to Bedford tonight is being asked to "Take It To The Bridge".
A special performance by CC Smugglers will take place at the town's Suspension Bridge on The Embankment from 18:30.
It's your chance to see a BBC Introducing band who will be supporting The Boss, Bruce Springsteen on his upcoming tour.
The whole event is all part of the second annual BBC Music Day.
Police constable dismissed after misconduct hearing into paralysed moped rider
Andrew Woodger
BBC News
One officer has lost his job, while another has been issued with a warning at the end of a police misconduct hearing.
The hearing was told the officers seemed more interested in making an arrest than helping a boy who had come off his moped following an incident where he was riding it on a footpath in Hemel Hempstead.
PC Stuart Francis has been instantly dismissed after being found guilty of gross misconduct.
PC Rishi Patel was found guilty of misconduct and received a written warning from Hertfordshire Police.
War time computer re-enactments take place at Bletchley Park
Nick Higham
BBC Correspondent
How do you crack Hitler's most secret cipher?
For the first time ever, all the equipment used in making and breaking the German Lorenz cipher has been demonstrated and re-enacted at The National Museum of Computing at Bletchley Park.
The demos included encrypting and decrypting messages using original and reconstructed equipment in the presence of re-enactment Wrens and cryptanalysts.
Among them was Irene Dixon (pictured below), one of the very first Colossus Wren operators.
I had the great pleasure of interviewing her and she told me they realised they were working in codes, but didn't know they were working on "Hitler codes".
More from the police misconduct hearing
PCs Francis and Patel denied using excessive force on the injured boy and of providing dishonest or misleading accounts of what happened.
One witness, Lisa Sandridge, told the hearing: "His [PC Francis's] behaviour was terrible. He didn't show any concern.
He gave him no first aid. "PC Rishi Patel was kneeling on Christian-Lee's legs as he was worried he was going to be kicked in the face. "Christian-Lee was in no state to be kicking anyone in the face."
The hearing in Hatfield is yet to decide what action will be taken against the two officers.
Misconduct hearing finds police officers guilty
Nicola Haseler
BBC Three Counties
Christian-Lee Thompson, now aged 16, was left paralysed and with brain damage after the incident on a disused railway line in Hemel Hempstead in July of last year.
He didn't have a helmet on at the time and was riding in an area only meant for walkers and cyclists.
The officer denied trying to arrest him using unnecessary force and providing misleading accounts of what happened.
PC Stuart Francis was found guilty of gross misconduct and PC Rishi Patel of misconduct.
Police officers guilty of misconduct for using force on injured teenager
Nicola Haseler
BBC Three Counties
A Hertfordshire police officer has been found guilty of misconduct over their use of force when a teenager was injured while coming off a moped.
PC Stuart Francis was found guilty of gross misconduct at a police disciplinary hearing over the way he dealt with 15-year-old Christian-Lee Thompson.
PC Rishi Patel was found guilty of misconduct.
BreakingHertfordshire police officers found guilty at misconduct hearing
Two Hertfordshire police officers have been found guilty at a misconduct hearing today.
It comes after a boy left paralysed after being knocked off his moped was held to the ground by police.
More to follow.
Residents 'furious' after human waste left behind after travellers leave
Matt Lockwood
BBC Three Counties Radio
I've been talking to a very angry Richard Roberts, who lives in Dunstable close to where a group of travellers have left tonnes of rubbish behind after leaving a site in the town.
He says there's human excrement on the nearby cycleway, adding if he did a quarter of the damage left he'd be "arrested".
He told me the matter has been going on for months and the council needs to "find them a plot of land" and "sort it out."
Clean up operations at Dunstable travellers' site expected to take several hours
Matt Lockwood
BBC Three Counties Radio
Council workers are currently cleaning up a high amount of rubbish left behind by travellers in Dunstable.
The team from Biffa waste management are expected to be finished this afternoon.
The mess was left after a number of caravans left the site last night.
Travellers leave tonnes of rubbish behind in Dunstable
Matt Lockwood
BBC Three Counties Radio
More than 1.5 tonnes (1500kg) of rubbish have been left behind by a group of travellers in Dunstable.
I've seen the waste, which includes human excrement, and was left at a skatepark behind the Grove Theatre in the town.
There's also tyre damage on surrounding fields.
Fire in disused building at Bletchley Park
Alex Pope
BBC Local Live
There's been a fire in an unoccupied building at Bletchley Park.
It's been confirmed to us that it wasn't one of the buildings on the heritage site, but was a derelict building dating from 1943. It was an extension of Block D.
Crews from Bletchley, Great Holm, Newport Pagnell and Winslow attended.
When the England team came to Aylesbury
BBC Sport
Twenty-eight years ago a bit of history was made in Aylesbury...
The England team came to Buckingham Road to complete their preparations for Euro '88.
You might even spot a rather younger Gary Lineker in his pants... a sight we may or may not see again soon on Match of the Day.
Video content