Newly released evidence adds to the theory that MoD scientist Dr David Kelly was murdered and did not commit suicide, an MP has claimed.

Norman Baker revealed that the penknife Dr Kelly apparently used to slash his wrist did not carry his own fingerprints.

Lib Dem Mr Baker said: "The angle you pick up a knife to kill yourself means there would be fingerprints.

"Someone who wanted to kill themselves wouldn't go to the lengths of wiping the knife clean of fingerprints.

Advertisement"It is just very suspicious. It is one of the things that makes me think Dr Kelly was murdered. The case should be re-opened."

UN weapons inspector Dr Kelly, 59, was found dead near his Oxfordshire home in 2003, days after he was named as the source of a BBC story that claimed the Government had "sexed up" a dossier on Iraq's weapons of mass destruction.

The dossier said Saddam Hussein could launch conventional nuclear or biological weapons within 45 minutes.

Independent doctors have said neither the cut to Dr Kelly's wrist nor the drugs found in his body were enough to kill him.

And they claimed the official cause of death, a severed ulnar artery in the wrist, was extremely unlikely to be fatal.

Mr Baker, who is writing a book on Dr Kelly, used the Freedom of Information Act to discover from Thames Valley police that no fingerprints were on the penknife. The MoD germ warfare expert was not wearing gloves nor were any found at the scene.

An inquest ruled his death was suicide and the Hutton Inquiry exonerated then-PM Tony Blair.

Dr Kelly's former colleague, UN weapons expert Richard Spertzel, claimed the scientist was on Saddam's hitlist because his work in the 90s had forced Iraq to admit to a secret biological arsenal.

A Thames Valley police spokeswoman said: "There were no fingerprints on the knife.

"This, however, does not change the official explanation for his death."

Dr Kelly's wife Janice has said she is certain he committed suicide.

She refused to comment on Mr Baker's murder theory.