Four current and former detectives have been told they will not face criminal charges over claims a rape investigation was mishandled.

The Independent Police Complaints Commission announced today that two serving and two retired detectives were no longer under criminal investigation.

However, the four bobbies and a fifth officer still face possible internal disciplinary action by Greater Manchester Police.

An IPCC probe was started in January after a coroner halted an inquest into the death of Stephen ‘Aki’ Akinyemi who died from head wounds after being shot in a violent tussle with businessman Arran Coghlan .

The fight happened at Mr Coghlan’s home in Alderley Edge.

The coroner referred the case to the watchdog after Mr Coghlan claimed the police had enough intelligence to charge Mr Akinyemi for an alleged knifepoint rape just days before the fatal struggle - but failed to do so.

An IPCC statement said: “GMP officers alleged to have mishandled a rape complaint have been told that they are no longer under criminal investigation by the IPCC.

"In March this year two serving detectives – a Detective Inspector and a Detective Constable; a retired Detective Inspector; and a retired Detective Constable now serving as a civilian with the force - were served with criminal notices alleging they failed to carry out the investigation to the correct standards and failed to provide adequate support to the victim.

“The IPCC has not identified sufficient evidence to establish that any of the four officers committed a criminal offence, and therefore a formal referral to the Crown Prosecution Service (CPS) will not be made.

“The IPCC will now determine if the four officers and a police constable who was not served with a criminal notice have a case to answer for misconduct.”

The investigation began after the IPCC learned that a complainant reported being raped at knife-point in 2010 but alleged that the incident was not investigated properly by the force and that a man identified as being responsible was never arrested or interviewed.

The inquest into Mr Akinyemi’s death was halted in March last year.

In August 2012 the coroner held a pre-inquest review and said the scope of the inquest should be narrow, meaning not all the evidence should be considered.

Mr Coghlan challenged her decision and in a judicial review claimed that officers knew he was mediating in a row between Mr Akinyemi, 44, and another man.

He also suggested police ‘knew of the extreme violence of which Mr Akinyemi was capable’.

Court documents state Mr Coghlan claimed: “The alleged rape for which there was sufficient evidence to charge presented a perfect opportunity to remove a dangerous and violent criminal from circulation.”