CRAIGAVON, Northern Ireland (CNN) -- Two men have been arrested in connection with the killing in Northern Ireland of a police officer, police announced Tuesday.
Forensic officers work the crime scene where Constable Stephen Carroll (right) was killed.
Constable Stephen Paul Carroll was gunned down on duty Monday night -- the second deadly attack on security forces in three days -- raising fears for the Northern Irish peace process.
The men, aged 17 and 37, were arrested separately "as a result of searches in the area," said a police spokeswoman, correcting her earlier statement that the first suspect was 18 years old.
Police have been raiding houses in Craigavon, the town where Carroll was killed, knocking down doors with hand-held battering rams, CNN's Atika Shubert reported from Craigavon.
Shortly after announcing the arrest of the first man on Tuesday, officers broke into a house near the site where Carroll was shot. Watch the manhunt under way »
The men were arrested between 4 p.m. and 5 p.m. (12 noon and 1 p.m. Eastern Daylight Time.)
The Continuity IRA, a republican splinter group that does not accept the Good Friday agreement, claimed it had killed Carroll, Britain's Press Association reported. Watch more about the dissident threat »
Carroll was shot dead late Monday, just two days after two British soldiers were killed at a military base in Northern Ireland, authorities said.
Carroll was the first police officer killed by paramilitaries in Northern Ireland since October 1998, the police said. The soldiers killed Saturday were the first British troops killed in the province in 12 years.
Police said Carroll was shot in the head in Craigavon, southwest of Belfast.
He was one of four officers who responded in two patrol cars to a call "from a terrified member of the community" about 9:45 p.m. (5:45 p.m. ET), Chief Constable Hugh Orde told reporters.
Carroll's vehicle came under fire and he was killed. "It's sadly as simple as that," Orde said, adding that the other officers were unharmed. Watch how the Continuity IRA claimed the killing »
The shooting left "a wife without a husband, a son without a father, and grandchildren without a grandfather," Chief Superintendent Alan Todd, the top local policeman, told reporters Tuesday.
"Stephen had given 23 years of service to the community working with the police service," Todd said.
He said a man in a light-colored top was seen running from the area after the incident, and appealed for information from the public about the shooting.
The killing of Carroll and the two soldiers on Saturday raised concerns that Northern Ireland could plunge back into the cycle of violence that ended after the Good Friday Agreement in 1998.
The two British soldiers were killed at an Army base in Massereene, in County Antrim, as they were preparing to ship out for duty in Afghanistan. Watch how the soldiers were killed »
The victims -- Cengiz "Pat" Azimkar, 21, and Mark Quinsey -- had already packed their bags, changed into desert uniforms and were awaiting a final pizza delivery when they were attacked, authorities said.
Two masked gunmen with automatic rifles shot the soldiers as the pizzas arrived at the barracks, authorities said. Two other soldiers and the two pizza deliverymen were seriously wounded.
Another militant splinter group, the Real IRA, reportedly claimed it had carried out the attack on the soldiers. Learn more about the Northern Ireland conflict »
Monday's shooting at the working-class Craigavon neighborhood seemed to underscore mounting tensions there in recent months. The area is known to harbor dissidents, and it experienced rioting and raids last year as police hunted for suspected terrorists.
"I think what we're seeing is a growing realization by a very small number of people that see Northern Ireland is going in a positive and peaceful direction -- their attempt is to derail that," Orde, the chief constable, said.
The shooting was quickly condemned by political parties, saying both incidents over the past few days are a threat to peace.
Officials with Sinn Fein, a predominantly Catholic party that seeks for Northern Ireland to leave the United Kingdom and become part of the Republic of Ireland, also spoke out against the attack. The party is widely thought to be linked to the Irish Republican Army.
Sinn Fein deputy leader Martin McGuinness called the killers "traitors to the island of Ireland."
The town of Craigavon has graffiti reading "C-IRA" and "Don't join Sinn Fein," an apparent rejection of the party's decision to join the peace process and Northern Ireland's power-sharing government
Danny Kennedy, deputy leader of the loyalist Ulster Unionist Party, said: "These terrorists seem totally incapable of understanding that they are flying in the face of the overwhelming will of the people in Northern Ireland, Great Britain and the Republic of Ireland, who want peace and political stability."
The shootings sparked fears of a return to the sectarian violence that Northern Ireland, a province of the United Kingdom, suffered for two decades before that.
The conflict was between unionists, who are mostly Protestant and want to remain part of the UK; and republicans, who are mostly Catholic and want to join the Republic of Ireland.
For nearly 30 years, British soldiers patrolled Northern Ireland in armored vehicles and hunkered down in bases surrounded by concrete walls and barbed wire. Violence spilled over into Britain, with the Irish Republican Army, known as the IRA, bombing London and other British cities.
Northern Ireland now has a power-sharing government and a prevailing peace that had been welcomed by all but radical splinter groups on both sides.
CNN's Jonathan Wald and Carol Jordan in London and journalist Peter Taggart in Northern Ireland contributed to this report
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