A COMPLAINT has been made against police who arrested a vulnerable man days before he apparently killed himself.

Friends and family of Adam Stanmore are appealing for anyone who may have witnessed his arrest on May 18 in Greater Leys to come forward amid fears that what happened contributed to his poor mental state.

It comes as the inquest into the death of Mr Stanmore opened yesterday, where his probable cause of death was confirmed as hanging.

The 37-year-old had been missing for nearly four weeks when his body was discovered in woodland off Grenoble Road at 3.40pm on June 13.

Close friend Bartek Piasta, who works as a solicitor, is investigating the level of force which may have been used by officers during the incident and accusations Tasers were deployed while Mr Stanmore was in the midst of a mental breakdown.

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Thames Valley Police has confirmed it is investigating a complaint but has refused to divulge any further information, including why Mr Stanmore was arrested.

A spokesman for the force, said: "I can confirm that a complaint has been made about an arrest on that date and at that location, however we do not confirm the names of people arrested.

"The complaint is being investigated by Thames Valley Police’ Professional Standards department. The matter has not been referred to the Independent Office for Police Conduct."

Mr Stanmore, who was homeless and unemployed at the time, was reportedly severely unwell in the days before his disappearance.

He had been sat on a wall in Acacia Avenue, Greater Leys, for much of the afternoon before officers arrived.

What happened next has not been confirmed but witnesses say there was an altercation during which he was shot in the legs and neck with Tasers and then pinned to the floor 'with force' by up to six officers.

Mr Piasta said he believes his friend was arrested for possessing a blade, but was not charged.

He understands he was then put in an ambulance but, at some point, told paramedics he wanted to get out and walked off - the last time he was seen alive.

He said: "Mr Stanmore was suffering with mental health issues at the time and needed help.

"I want anyone who may have seen what happened to get in contact with me."

Mr Piasta's complaint against the officers was filed on June 20.

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On June 21 he received an acknowledgement that an investigating officer was going to be assigned to the case and that it would be 'comprehensively and thoroughly investigated' and he would be kept updated throughout.

Since then he has heard nothing, despite possessing a number of witness statements which could help piece together what happened.

Before his body was found, friends frantically searched for Mr Stanmore, amid hopes he was still alive.

His disappearance was reported four days after his arrest, on May 22.

During the search, Detective Inspector James Senior released a statement saying: “I have a message for Adam, if you see this, you are not in any trouble.

“It is very important we find out where you are as the police and, of course, your family, are concerned about your welfare."

At a brief hearing in Oxford Coroner's Court yesterday, assistant coroner Nicholas Graham opened the inquest into Mr Stanmore's death.

He read a brief report and said enquiries were continuing but the probable cause of death was 'hanging'.

The inquest will resume on January 8 at 10am.