Detectives in London yesterday arrested a man believed to be an unemployed musician on suspicion of the murder of the BBC television presenter, Jill Dando, in an early morning operation which included a search of the suspect's home.
Detectives were continuing to question the man, believed to be in his 30s or 40s, last night but Scotland Yard said charges were not imminent and the interview process is expected to be lengthy.
The arrest of the man, who has not featured in the investigation until recently and is not believed to have been known to Ms Dando, is being described by police as "highly significant" as he is the first person to be arrested on "suspicion of murder".
The man was arrested at his home in London, where he lives alone, at about 6.30 a.m. He offered no resistance and was taken away for questioning to a London police station.
Ms Dando's father, Mr Jack Dando, said he was "optimistic" about the development: "Twelve months I've waited to hear a message like this. It's just terrific. But I suppose it's still early days. I'm highly elated but at the same time a bit cautious because we've been here before, with them arresting someone and then releasing them without charge. But he's been arrested for murder rather than just `helping police with their inquiries'. I'm more optimistic."
The presenter's brother, Mr Nigel Dando, said police had informed him of the arrest in a telephone call, but he did not have any further information. Ms Dando's fiance, Mr Alan Farthing, declined to comment on the arrest.
The development came 13 months after Ms Dando was shot in the head on the doorstep of her Fulham home in south-west London on April 26th, 1999, after returning from a shopping trip.
Her murder prompted a huge police investigation. Over the last 13 months the 50-member investigating team has interviewed 100 suspects and has received 8,000 telephone calls from the public offering assistance. However, Scotland Yard yesterday refused to comment on reports that the man in custody had been under surveillance for several weeks prior to his arrest or that the arrest was made after a renewed appeal for information was broadcast on the BBC Crimewatch programme, which she presented.
The investigation into the murder has been complicated by the fact that no eye-witnesses to the killing have come forward and a definite motive has yet to be identified. An initial theory that the murder may have been connected to the conflict in Kosovo was quickly discounted and the investigation then considered whether Ms Dando's murder was a contract killing connected with her Crimewatch work.
Officers spent several months attempting to trace a blue Range Rover that was seen close to her home at the time of the murder but have been unsuccessful.
However, in recent months the investigation has concentrated on the theory that an obsessive fan was responsible for the killing. Only last month, on the first anniversary of the murder, detectives announced they had identified at least 140 people who had an "unhealthy interest or obsession" with the presenter.