The top police officer called in to probe claims that Met Police undercover officers targeted grieving families said there was no policy to do so.

But Chief Constable of Derbyshire Police, Mick Creedon, said errors had been made including the retention of information for far longer than necessary.

He said information had been gathered on some 18 families, in what he described as 'collateral intrusion'.

His press conference at New Scotland Yard, to update the media on the progress of Operation Herne, a probe into allegations that undercover Special Demonstrations Squad (SDS) officers spied on grieving families such as that of murdered black teenager Stephen Lawrence, came the day after the mother of a Brunel University student found dead in the River Thames raised fresh concerns.

Sukhdev Reel, the mother of Ricky Reel, said yesterday (Wednesday, July 23) she had been told SDS officers had spied on the family.

Ricky, then 20 and living with his family in West Drayton, died in October 1997 in suspicious circumstances, following an apparent racist attack on Ricky and his friends while they were on a night out in Kingston-upon-Thames.

A campaign was started soon afterwards calling for an enquiry and justice.

Speaking at the press conference, Assistant Commissioner of the Met, Martin Hewitt, said: “This is a difficult and incredibly emotive subject to talk about, and there will be a number of families out there for whom this has caused much distress.

“I was moved by the interviews with Mrs Reel last night, and that is why it is so important that we are all clear about the facts of what happened.”

Mr Creedon will publish his report soon. He was not prepared to elaborate on which families might have been affected, stating: “We have made or are in the process of making contact with legal representatives for those families and people affected to brief them on what we have found.”

“I am not prepared to name those families or individuals. This is covered in my report”

“In explaining why I am not prepared to name the families and the campaigns, firstly we have not managed to meet with all the relevant families, but secondly it is not my role to potentially cause them more distress by placing this detail in the public eye. They have already suffered enough.”

“My investigation will continue to examine how this came to be and if there are misconduct matters by officers we will identify them.”