UPDATED 11 a.m. - An elderly woman was fatally stabbed at her home in Cospicua in 1986 because three men who entered her house to rob her feared being identified, a court was told this morning.

The court was hearing testimony before a jury decides whether the accused, Saviour Mangion, 47, is mentally fit to stand trial for the murder of Maria Stella Magrin on October 29,1986.

Mangion is already in prison serving a life sentence for the murder of Rosina Zammit, 54 in Safi in 1984. He was also jailed for 21 years for the murder in 1998 of Francis Caruana.

Police Inspector Chris Pullicino who had investigated 'cold' cases, told the court that in May 2005 he received information that the accused was involved in the Magrin murder.

The accused at first denied involvement, but then admitted and gave a very detailed account.

He had described how a screw driver and a knife were used in the stabbing.

He took policemen to the area near the Realto Theatre, describing how the three men - himself and Oswald and Leli Spiteri - had parked their Morris Marina there. They then walked to the house where the murder took place. The house had since seen structural changes  but the accused described the house and how the theft took place.

Oswaldo Spiteri had admitted his involvement and repeated what Mangion said. The only thing that it didn't match was that Mangion said that both of them stabbed her but Mr Spiteri denied this. Leli Spiteri had died in 2000.

Mangion knocked on the door and the victim opened without asking who it was. They went upstairs, robbed her and killed her.

"He killed her because she would otherwise identify him",the inspector said.

Mr Mangion had been described as Malta's serial killer by Mr Justice Joseph Galea Debono after his second conviction.