England's former top policeman yesterday launched a vitriolic attack on ex-Home Secretary David Blunkett.

In a book serialised in the News of the World, former Metropolitan Police Commissioner Lord Stevens described his difficult relationship with Mr Blunkett during his time at the Home Office, accusing him of knowing little about policing.

He accused Mr Blunkett of using the September 11 terror attacks in the US to score cheap political points.

And he claimed that the MP - who resigned from the Cabinet last December only to return as Work and Pensions Secretary after the May general election - had accused police of "over-reacting" to the terror threat less than two years before the July bomb attacks in London.

Lord Stevens alleged that Mr Blunkett destroyed the good work done by his predecessor Jack Straw in boosting Government relations with the police.

"For years I had absolutely no problems with Michael Howard nor with Jack Straw," he said.

"Then, in the form of David Blunkett there came along a new Home Secretary who knew very little about policing. Many felt he took office ready-armed with an anti- police agenda."