A POLICE investigation into the abduction of a man who was later tortured and decapitated was ‘flawed’, a watchdog said today.

Michael Gilbert, 26, was taken from the street outside the Job Centre in Blackburn in January 2008.

But an incorrect mobile phone number was written down by the officer who took details of the incident from concerned relatives.

When police phoned the number they got the wrong man and concluded falsely that Mr Gilbert, who lived in Blackburn, was avoiding contact and had left of his own accord.

Seventeen months later three people were convicted of Mr Gilbert’s murder.

The court heard he had been kept as a slave and tortured for his benefit money, before his body was dumped in a Bedfordshire lake.

Mr Gilbert’s mother had made the complaint about the police believing her son’s murder could have been prevented.

She highlighted the abduction investigation and two other probes involving other forces.

The Independent Police Complaints Commission (IPCC) report concluded the Lancashire police investigation was flawed.

But the IPCC said the police conclusion that Mr Gilbert was avoiding contact was a reasonably held belief on the basis on the information available.

And the IPCC said it was not possible to say whether the number was incorrectly provided to the officer or mistakenly written down.

A Lancashire Police spokesman said the force followed the correct guidelines and stressed that the IPCC did not find the investigation was carried out improperly.

Bedfordshire and Cambridgeshire police forces were also investigated over incidents involving Mr Gilbert before his death.

The IPCC said a 2002 assault investigation in Luton was hampered after it was given inaccurate information from other public services and a 2007 Cambridgeshire abduction inquiry was ‘hindered’ by a Bedfordshire officer not passing on information to the force.

IPCC Commissioner Rachel Cerfontyne, said: “This is a tragic case and one where the horrific manner of Michael's death must make it even harder for his loved ones to cope with their loss.

"I extend my sympathies to them.

"We looked at specific allegations that the police did not investigate three incidents involving Michael and the Watt family.

"We have found that on each occasion investigations had taken place, but were flawed due to misinformation, failures in communication and human error.”

During the murder trial, the court heard how ‘vulnerable’ Mr Gilbert was hit with bats, shot, and stabbed. Beatings were often filmed on mobile phones.

On one occasion he was made to goad a large pet lizard until it attacked him with its tail, and one defendant’s diary included plans for a game show where contestants would pay £5 to slap him and £25 to headbutt him, the court heard.

Mr Gilbert escaped several times but they would track him down and force him to come back.

Detectives believe Mr Gilbert died overnight between January 21 and 22, 2009, as a result of the abuse he had suffered.

A bag containing his headless corpse was found by two dog walkers on May 10, 2009, weighted down with a stone from a patio wall.

His knee joints, forearm and elbow were missing, as well as his head.

Mr Gilbert's severed head was not discovered until February 2010 in a prison-issue holdall, along with other missing body parts.

A Lancashire Police spokesman said their thoughts were with Mr Gilbert’s family, adding: “It is important to point out that the complaint against Lancashire Constabulary was not upheld as the IPCC determined that we had not failed to properly investigate the reported abduction.

“From the initial report on February 1, 2008, through to the conclusion of the inquiry the Constabulary followed the correct guidelines, made the necessary enquiries and made reasoned decisions based on the information we had.

“As far as the discrepancy with the phone number is concerned, the IPCC concluded that this was a genuine mistake by either the informant or the officer while passing or taking down the information.

"Both the officer and informant had Michael's best interest in mind judging by their actions on the day.”