Police have uncovered fresh evidence that television presenter Jill Dando was killed by a stalker obsessed with her.

Investigations have revealed a number of men exhibited fixated behaviour towards 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.

The presenter, 37, was shot once in the head on 26 April on the doorstep of her home in Gowan Avenue, Fulham, west London.

The latest information was released on Thursday by a source close to police inquiry.

Miss Dando also featured in websites in mocked-up nude poses, and police are still being contacted by work colleagues and friends of people who appear obsessed by Miss Dando.

There are still 22 "mystery men" seen around the time of the murder in her road who have not been traced, the source indicated.

Eleven of those had been identified by detectives as being suspicious or having descriptions which match a man seen walking from Miss Dando's home in Gowan Avenue at the time of her murder.

Detectives have also released further details of the weapon used to kill Miss Dando.

They say the 9mm pistol was of a type rarely used in such crimes and it had been altered.

The latest information follows a report that an innocent man had been followed for weeks by detectives after being wrongly named by an informant as the person who gunned her down.

The Sun newspaper said police had spent �500,000 trailing the suspect, who had now been eliminated from the inquiry, but Scotland Yard has refused to confirm the claim.

"Officers investigating the murder of Jill Dando are pursuing a large number of lines of inquiry and have never concentrated all of their resources into one avenue," a spokeswoman said.

"Detective Chief Inspector Hamish Campbell and his team remain confident and continue to work through the mass of information that has been fed in to the incident room."