AN investigation has been launched into claims that a weapon used in a murder of a Southampton man had previously been handed in to police during a knife amnesty.

Winchester Crown Court heard how a blade, used to inflict fatal wounds on Neil Hampson, could have been among a collection surrendered earlier.

Jurors were told how knives had been stolen from former police civilian worker John Goodenough's home by killer Tony Wilkinson, 28, who was jailed for life on Friday.

Wilkinson's ex-girlfriend Amanda Reeves had been a carer for Mr Goodenough's disabled daughter and often stayed at the family's home.

Tragedy struck on November 3, 2007 when knife-obsessed Wilkinson stabbed 32-year-old Mr Hampson up to 20 times in the heart and neck at a party at Havre Towers in Weston.

The court was told how Wilkinson kept a bag of more than 20 knives at Miss Reeves' Verwood flat.

Wilkinson and Mr Hampson both attended a 21st birthday party.

On their return to Wilkinson's girlfriend's flat at Weston, Southampton, violence flared.

When Mr Hampson collapsed, Wilkinson fled, threatening two men in the street at knifepoint before fleeing to Bournemouth.

Wilkinson from Merrow Avenue, Poole, was arrested at Miss Reeves' flat.

She told jurors how she had dumped his knives in a nearby wood and admitted perverting the course of justice.

Mr Hampson died at Southampton hospital 90 minutes after the attack.

Judge Peter Rook QC recommended that Wilkinson should serve a minimum of 17 and a half years behind bars.

After the verdict, DI Darren O'Callaghan from Hampshire police said Mr Hampson's death "could have been easily avoided and shows clearly the dangers of carrying a knife."

A Dorset police spokesman said: "Whilst the murder weapon has never been identified, during the course of the investigation a number of knives were seized by detectives.

"It was alleged during the trial that some of these knives may have been stolen from Dorset police by a member of staff after having been handed in during a knife amnesty.

He said that"An investigation into the circumstances surrounding the recovered knives is being undertaken and whilst ongoing it is not appropriate to discuss the matter further.

"It may identify potential areas to improve security surrounding knife amnesties."