DUBLIN, Ireland (AP) _ A newspaper journalist who covered Dublin's crime world was shot to death Wednesday when two men on a motorcycle ambushed her car at a traffic light.

Veronica Guerin, 33, was killed instantly after being shot several times with a handgun in Clondalkin, a suburb southwest of Dublin, police said.

Guerin had been attacked before, but had said that would not deter her from continuing as an investigative reporter for the Sunday Independent. Tight security was installed at her home after earlier attacks, but she insisted on pursuing stories alone, carrying only her pen and paper.

Prime Minister John Bruton condemned her killing in an address to Ireland's parliament, the Dail, saying it was ``an attack on democracy as a whole because it is an attack on one of the pillars of our democracy.''

``The murder of a journalist in the course of her work is sinister in the extreme,'' Bruton said. ``Someone, somewhere decided to take her life and almost certainly did so to prevent information coming into the public arena.''

A union of mid-level police officers _ The Association of Garda Sergeants and Inspectors _ expressed revulsion at Guerin's slaying. They said she had won their respect for ``her exposure of some of the criminal scum who are feeding off our society like parasites.''

Guerin had been shot in the thigh at her home in Dublin in January 1995. In September, she was bruised in a beating. No one was arrested in either attack.

``It matters, what we do,'' Guerin said in December, when she received an International Press Freedom award in New York from the Committee to Protect Journalists. The committee was founded in 1981 to monitor abuses against the press and to promote freedom of the press around the world.

``If I didn't think my work made a difference,'' she said, ``I'd probably give it up.''

Police issued physical descriptions of the two attackers and said late Wednesday they were directing their initial investigation toward a criminal gang in south Dublin.

Guerin is survived by her son, Cathal, 7, and her husband, Graham Turley.