A police chief told officers to "arrest first" and investigate later when dealing with rape cases, it has been reported.

Lynne Owens, who is head of the National Crime Agency, is said to have made the changes when she was chief constable for Surrey Police.

However, a man who was arrested "without a shred of evidence" after being accused of rape said the tactics had a "catastrophic effect" on his life.

According to the Sunday Times, minutes from a September 2015 meeting reveal that Owens, who is tipped to become the new Metropolitan police commissioner, was asked how the force was trying to improve their detection rates for rape.

The minutes record: "The chief constable was keen to ensure officers were robustly pursuing offenders. Officers tended to receive an allegation then wait to make an arrest after gathering evidence. They needed to change this and make an arrest first and then gather the evidence."

Deputy chief constable Nick Ephgrave, who now leads the force, told the meeting that the tactics had raised the rape detection rate from six per cent to 15.8 per cent in a year.

An NCA source said that the comments were not necessarily direct quotes and were part of a discussion on the safe-guarding of victims in the wake of a rape review by Her Majesty's Inspectorate of Constabulary.

They added it was "inaccurate" to suggest that the approach was taken in order to boost figures.

However, a 49 year-old Surrey resident who was arrested over claims he had raped his former partner abroad said he spent four weeks on bail before being told he would not be charged.

He said: "There was not a shred of evidence in my case. "Unless you have been in this situation you cannot believe the impact it has on your life. This approach is out of control."

NCA Director General Lynne Owens said: "My comments when I was Surrey's Chief Constable were made in the context of internal and external reviews when we were not always getting the balance right between making an early arrest to support the safeguarding of victims and where we were waiting for all the evidence to have been gathered before making an arrest.

"Every case was taken on its merits though and both those things weighed."

Surrey police also said the timing of an arrest was considered on a "case by case basis."

A spokesperson said: "Early arrests may be necessary in order to secure and preserve evidence. This evidence can include the suspect's accounts in respect of the offence, or forensic evidence from the suspect or scene, or other evidence relating to the offence which could be interfered with or disposed of.

"In addition to this, the investigator would also take into account the risk posed by the alleged offender to the victim or other persons."

Surrey police faced criticism after interviewing Jimmy Savile in 2009 in relation to accusations of sexual offences.

Savile was not arrested but it emerged after his death that the DJ had abused hundreds of children over four decades, including at least 22 students at a Surrey school.