Two soldiers were shot dead and another two seriously injured on Saturday night, raising fears that dissident republicans are bringing violence back to the streets of Northern Ireland.

The Sunday Times said that the soldiers were understood to be taking delivery of a pizza when their attackers pulled up in a vehicle and opened fire outside the barracks of 38 Engineer Regiment in Antrim.

Two civilians were also seriously hurt.

The soldiers are the first to be killed in Northern Ireland for 12 years.

The attack happened at Massereene Barracks on the edge of the town, which is 16 miles northwest of Belfast, at 9:40 p.m..

Eyewitnesses said there were two long busts of gunfire. One witness, who lives near the base, said at first he thought it was fireworks. "Then I heard a lot of loud bangs again, only it was a lot more than there was initially -- maybe between 10 and 20."

Ireland's public broadcaster RTE said the attackers got past the base's checkpoint in a taxi and opened fire with machine guns.

All six victims were taken to Antrim hospital a mile away. The area around the barracks was sealed off and a major security operation was underway early Sunday.

"This is a terrible reminder of the events of the past," said Peter Robinson, Northern Ireland's First Minister and Democratic Unionist Party leader. He and other politicians vowed the gunmen would not succeed.

Suspicion will focus on the Real IRA, the breakaway republican group responsible for the Omagh car bombing in 1998 in which 29 people died.

Their deaths came just 36 hours after Sir Hugh Orde, the Northern Ireland chief constable, confirmed that undercover soldiers from the Special Reconnaissance Regiment (SRR) had been called in to carry out surveillance operations on dissidents amid warnings that the threat against his officers and military personnel was at its highest for almost a decade.

The Real IRA is believed to be rearming and reorganizing over the past year. Last month it abandoned a 330 pound car bomb in Castlewellan. The terrorist group said it had been thwarted in itsaim of causing major loss of life at an army base.

Gordon Brown, the Prime Minister, joined with Irish Prime Minister Brian Cowen in condemning the attack."In recent days action has been taken to increase security in Northern Ireland," said Mr Brown in a statement. "This is because of the increased threat from those who, even at this late stage, wish to ignore the wishes of the overwhelming majority of the people of Northern Ireland and attempt to derail the peace process."

Cowen said: "A tiny group of evil people cannot and will not undermine the will of the people ... to live in peace together."

The last soldier killed in the Troubles was slain in Bessbrook, Co Armagh, where a sniper shot Lance Bombardier Stephen Restorick, 23, through the neck as he chatted to a villager at a road checkpoint in February 1997.

(Xinhua News Agency March 9, 2009)