'Lessons learnt' in Nickell case

Lessons have already been learnt from the blunders which delayed the capture of sex killer Robert Napper, police said.

The Metropolitan Police has apologised for its mistakes which saw innocent loner Colin Stagg named as the prime suspect in the murder of young mother Rachel Nickell 16 years ago.

But the force refused to be drawn on whether a further inquiry would be held in the wake of Napper's guilty plea, saying only that inquiries had already been carried out.

"A number of reviews have taken place already," said a spokesman. "Homicide investigations have changed significantly since 1992 and we've learnt from these reviews."

Napper pleaded guilty at the Old Bailey to Miss Nickell's manslaughter on the grounds of his diminished responsibility and was ordered to be detained in Broadmoor indefinitely.

He could have been caught as far back as 1989 when his mother said he had confessed to a sex attack.

But police could not trace the crime and did not interview him or collect his DNA.

He went on to commit at least four more sex attacks before launching a brutal sex attack on Miss Nickell in which she was stabbed 49 times on Wimbledon Common in July 1992.