Five police officers are under investigation over an inquiry into a murdered pregnant teenager who was reported missing more than two weeks before her body was found.
Former Colne Primet High School pupil Jayden Parkinson was strangled by violent ex-boyfriend Ben Blakeley, 22, - 24 hours after she told him she was expecting his child.
The 17-year-old who had spent around a year living in Nelson with her father Paul, was murdered on December 3 last year.
Mr Parkinson, 48, died of a heart attack just days before the trial of his daughter’s killer was due to start.
Following Blakeley's conviction for murder, police watchdog the Independent Police Complaints Commission revealed details of its investigation into how Thames Valley Police dealt with the case.
Investigators are looking at what the force did between December 4, when the teenager was reported missing by staff at the hostel where she was staying, and December 12 when Blakeley was arrested on suspicion of murder and a major crime investigation was launched.
Her body was found on December 19 in a Blakeley’s uncle’s grave at the Great Western Cemetery next to All Saints' Church in Didcot, Oxfordshire.
Jayden had previously alerted police that her ex-boyfriend had indecent video and pictures of her that he was threatening to put on Facebook, and investigators are looking at whether the officers who questioned him over the claim on December 4 knew whether Jayden had been reported missing.
They are also examining why Jayden was first classed as a medium risk missing person, and then later moved to high risk on December 10.
Five officers have been served with misconduct notices to tell them that they are under investigation, and the IPCC team is in the process of interviewing them.
IPCC associate commissioner Guido Liguori said: "Jayden's family continue to go through an incredibly difficult time, and I again offer my condolences to them.
"Now that the murder trial has concluded, we can provide a clearer picture of our investigation and the progress that has been made in recent months in parallel with Thames Valley Police's criminal investigation.
"As well as examining the individual actions of officers and staff in response to Jayden being reporting missing and whether these were appropriate, our investigation has also been looking at the force's policies and systems around missing person reports.
"There is still work to do and it is vital that we establish as full a picture as we can as to how the force responded to Jayden being reported missing, and the contact officers and staff had with her and Ben Blakeley in the months before her murder."