BELFAST, Northern Ireland -- Police arrested two more suspected Irish Republican Army dissidents Monday in their investigation into this month's killings of British soldiers and police in Northern Ireland -- a wave of violence that a leading backer of IRA dissidents described as inevitable.
Anti-terrorist detectives were interrogating 11 suspects in total after police detained two men aged 27 and 31 in a Catholic part of Craigavon on suspicion of involvement in killing a police officer March 9 in the town southwest of Belfast.
Nine other suspects have been arrested and kept in custody over the past week over the policeman's slaying or the March 7 gun attack on off-duty troops outside the Massereene army barracks in Antrim, west of Belfast. Under British anti-terror laws they can be held up to 28 days before being charged or released.
Sinn Fein deputy leader Martin McGuinness -- a former IRA commander who is the senior Irish Catholic in Northern Ireland's power-sharing government with the British Protestant majority -- said he is confident both sides of the community are uniting to isolate the dissidents.
"People are not shaken. They understand this is an attempt to create mayhem in our society. It isn't going to succeed," McGuinness said.
But an Irish republican from Republican Sinn Fein, a fringe group opposed to the past 15 years of peacemaking, warned dissidents would be right to keep attacking British security forces and to resume bomb attacks on England itself.
"When the British government occupies another country, they do need to realize that consequences come with that," said Des Dalton, vice president of Republican Sinn Fein. It is close to the Continuity IRA, the splinter group that claimed responsibility for slaying the policeman.
Dalton said McGuinness had become a "traitor of the historic Irish nation" because he had accepted a job as "a minister of the British government" and had allied himself with "British colonial police."
The dissidents are trying to undermine the IRA's 2005 decision to renounce violence and disarm and Sinn Fein's efforts to persuade Catholics to cooperate with the police force -- once overwhelmingly Protestant but now more than 25 percent Catholic.
The 11 suspects include two well-known Irish republicans detained Saturday. The arrest of Colin Duffy, 41, triggered weekend riots by his largely teenage supporters in the town of Lurgan.
Police also arrested Declan McGlinchey, 32, son of Dominic "Mad Dog" McGlinchey, who once boasted of killing more than 30 people as leader of an IRA splinter gang called the Irish National Liberation Army. Former INLA colleagues killed him in 1994 in front of his son.
In the March 7 attack, two masked men with assault rifles fired more than 60 rounds at off-duty, unarmed soldiers collecting pizzas from two delivery men outside their base. Two soldiers died and four other people were seriously wounded, including both pizza couriers. A splinter group called the Real IRA claimed responsibility.
Two days later, a 48-year-old policeman was shot in the head after his unit responded to an emergency call from a woman whose home was being attacked by stone-throwing youths.
Analysts say the dissidents -- who have mounted more than 20 gun, bomb and rocket attacks since late 2007 -- hoped this month's killings would undermine the current U.S. visit of McGuinness and Peter Robinson, the Protestant leader of the power-sharing government.
The two leaders twice delayed their trip last week, but are scheduled to meet President Barack Obama at the White House and congressional leaders on Capitol Hill on Tuesday, St. Patrick's Day, an annual event cherished by Ireland's leaders north and south.