DUBLIN, Ireland (AP) _ The leader of the Irish Republican Army's legal political wing said the IRA killed an ''exceptional and regrettable'' number of civilians last year.

But Gerry Adams, president of the Sinn Fein party, told 600 delegates to the annual party convention that his rebuke did not mean he was condemning the outlawed IRA and its armed struggle to end British rule in Northern Ireland.

In Northern Ireland, meanwhile, a police officer was killed Saturday and two others injured in a bombing attack near the Irish Republic border.

And in London, an estimated 2,000 demonstrators marked the 17th anniversary of ''Bloody Sunday,'' when British soldiers fatally shot 14 people during a Roman Catholic civil rights protest in Northern Ireland.

Sinn Fein supports the mainly Roman Catholic IRA's fight to unite the province with the republic. But even some IRA supporters have criticized the group for blunders that killed at least 20 civilians in the past 14 months.

Adams earlier this year told the IRA to ''get its house in order'' after one of its bombs killed two of his Roman Catholic constituents in West Belfast.

''Since the last (convention), there has been an exceptional and regrettable level of civilian casualties and fatalities arising from IRA operations,'' Adams said in a keynote speech at Dublin's Mansion House.

''Our dismay, our regret and our sympathy with the plight of families bereaved by the IRA is genuine,'' he said.

Martin McGuinness, a member of Sinn Fein's national executive committee, told the conference the IRA is trying to resolve the issue.

He said the IRA dissolved one of its units to punish it after a November bombing in Enniskillen in which 11 civilians were killed.

Earlier, senior party official Danny Morrison said Sinn Fein may set up pirate radio stations in the n 1985. The next local elections are in May.

The convention is to end Sunday.

In Northern Ireland, meanwhile, a policeman was killed and two others were injured during a bomb attack in the border village of Sion Mills in west Northern Ireland.

A spokesman at police headquarters in Belfast said the three policemen were driving down the main street of the village when someone standing in the doorway of a pub signaled for them to stop.

Not realizing it was an ambush, the policemen halted their car and one got out to investigate. An assailant then threw a bomb at the car from the roof of a nearby building, wrecking the car, police said.

One officer died and another was badly hurt in the blast. A third was injured when scores of people spilling out of a nearby nightspot pelted him with bottles as he tried to aid his injured colleagues.

The noisy crowd also attacked army and police arriving on the scene but the group was dispersed when reinforcements fired rubber bullets, police said.

Police said the march in London went ''extremely well,'' and four people were arrested for public order offenses. Chief Inspector Roy Symons said about 50 supporters of the extreme right-wing National Front followed the march but there were no clashes.

The British Army said the soldiers opened fire on an illegal march organized by the Civil Rights Association in Londonderry on Jan. 30, 1972, in response to sniper fire. A judicial inquiry concluded that none of the dead or wounded had been proven to have been shot while handling a firearm.