Detectives hunting the killer of TV presenter Jill Dando say a gun has been found a gun close to the murder scene.

Scotland Yard confirmed the handgun, which was found shortly before midday on the foreshore of the Thames near Putney Bridge in west London, is being examined by forensic experts to see if it is the murder weapon.

It was reported that the weapon, discovered wrapped in newspaper by a film crew worker, was a 9mm Beretta - the type of gun used to shoot Miss Dando at point-blank range outside her Fulham home in April.

A Yard spokesman said: "We can confirm that a gun was found on the foreshore of the Thames and is now being analysed by the Forensic Science Service.

"Obviously officers involved in the Jill Dando inquiry are aware of this development but we are not discussing further details for operational reasons."

The gun was found, with the plastic parts of the handle removed, close to a spot where at least one witness at the time of the murder on 26 April reported seeing a man throwing something into the water.

Forensic tests

Officers have long believed Miss Dando's killer may have escaped across Putney Bridge, less than mile from her home on Gowan Avenue, possibly driving a blue Range Rover as a getaway vehicle.

The weapon, which did not have silencer with it, was reportedly found by a 35-year-old film crewman working on a scene for a new Disney film, 102 Dalmatians.

He told The Sun newspaper: "I was taking a midday stroll at low tide when I saw an object wrapped in newspaper. I opened it to find a black automatic weapon handgun.

"I knew that Jill Dando's killer escaped over Putney Bridge, so I thought this must be the handgun."

Despite the potential significance of the gun's discovery in the seven-month murder investigation, police were cautious about drawing any immediate conclusions.

The Yard spokesman added: "The weapon will be subject to close examination by forensic experts and it is likely to be some time before we know its significance."

The short semi-automatic handgun used to kill Miss Dando at her home had a smooth bore, indicating that it had been tampered with.

It could have been converted from a gun firing blank rounds, altered to get around the tightening of gun laws, or illegally reactivated after being taken out of commission under post-Dunblane legislation.

The discovery of the gun came on the day police revealed they had uncovered evidence boosting the theory that the Crimewatch presenter was killed by an obsessive stalker or crazed fan.

They said a number of men had exhibited fixated behaviour towards 37-year-old Miss Dando in the months before her death.

One man even pretended to be her brother in an attempt to get her electricity bill moved to his name.

On another occasion, a man contacted BT, giving Miss Dando's ex-directory telephone number and address and asking for her line to be changed to his name.

Detectives still believe that the stalker theory and the notion of an organised contract hit - perhaps sparked by Miss Dando's Crimewatch connection - are the most likely murder scenarios.