Wednesday, May 19, 1999 Published at 02:20 GMT 03:20 UK
'Good response' to Dando appeal
Ms Dando presented April's Crimewatch UK alongside Nick Ross
Click here to see how the tragedy unfolded
He said he was particularly interested in two calls from passengers on the number 74 bus, who overheard the prime suspect speaking on his mobile phone shortly after the murder.
Ms Dando was murdered with a single shot to the head outside her home in Fulham, west London on 26 April. Tuesday's edition of Crimewatch UK opened without titles or music and her former co-presenter Nick Ross said described the programme as "sombre and surreal".
He said: "It has been almost unbearable working on Jill's death."
But he added: "This programme was her passion and now, as Jill helped others, our help can do the same for her, her family and her fiancé Alan (Farthing)."
Mr Farthing told the programme: "Somebody has murdered the person I had hoped to spend the rest of my life with."
He said: "It's always difficult for anyone to cope if you don't know why something has happened. It just defies logic."
He said he believed the pair were probably different men but it was not clear if they were acting together. The prime suspect was a dark haired, heavily sweating man seen waiting at a bus stop in the Fulham Palace Road.
'Where did he go?'
Another man was seen sitting in a Range Rover close to Ms Dando's home on the morning of the killing.
A traffic warden was about to give him a parking ticket when he knocked on the windscreen to indicate he was about to drive off.
Mr Campbell said he needed to speak to both men to eliminate them from the inquiry.
He said: "They probably think they were there innocently and can't be any help.
"But we have to find them. It will help us to ascertain the motive, by working out how many people were involved in her murder."
He said it was still not clear whether the killing was a conspiracy or the act of a "loner".
'Does this sound familiar?'
"If it was a loner, maybe someone has noticed a friend or relative who had a fixation or fascination with Jill Dando. Was his behaviour different on that day?"
Mr Campbell also appealed for help on finding the murder weapon.
He said it was a 9mm "short" automatic, which was very different from the larger Browning gun.
At the end of the programme there was a tribute to Ms Dando.
'No hollow reassurances'
Nick Ross, wearing a solemn, dark suit, usually signs off the programme with his trademark "Don't have nightmares. Please sleep well."
He said "hollow reassurances" were incongruous in the wake of her death.
But Mr Ross added: "Her death was unprecedented. It was a one off and crime in Britain is still falling."
He said: "But we say it as we have always said it. Don't have nightmares. Do sleep well."
The service and burial will be attended by just her family and close friends.
Thousands of mourners are expected to line the streets of the town. The hearse will follow a three-mile route.