Timeline - Ups and downs of Northern Ireland peace process

BELFAST (Reuters) - The prime ministers of Britain and Ireland started a second day of talks on Tuesday to salvage a deal to keep Northern Ireland's fragile power-sharing government together.

Following is a timeline since a 1998 Good Friday peace deal ended three decades of violence that killed 3,600 people in the sectarian conflict.

June 1998 - Elections to a new Protestant-Catholic power-sharing assembly. Protestant Ulster Unionist Party (UUP) leader David Trimble is elected First Minister-designate.

August - Car bomb in the town of Omagh, west of Belfast, kills 29 people in the worst single attack of the conflict. The Real Irish Republican Army (IRA) splinter group claims responsibility.

December 1999 - Northern Ireland gets its own government in which Protestants and Catholics share power after 27 years of direct rule from London.

February 2000 - Britain suspends assembly amid anger by Protestants, who support ties to Britain, over the failure of IRA guerrillas to disarm.

May - IRA says it will put its weapons into storage and allow inspections. Britain restores power to Belfast assembly.

June 2001 - IRA political ally Sinn Fein overtakes its more moderate rival, the Social Democratic and Labour Party (SDLP), as Northern Ireland's biggest nationalist party in British parliamentary elections.

July - Trimble resigns over IRA's failure to disarm.

October - IRA says it has put some weapons "beyond use."

October 2002 - Sinn Fein offices at the Northern Irish assembly are raided by police investigating an alleged IRA spy ring. Britain suspends the assembly and resumes direct rule.

November 2003 - Election takes place with Ian Paisley's hardline Democratic Unionist Party (DUP) -- which opposed the Good Friday Agreement due to Sinn Fein's involvement -- overtaking the UUP as the province's biggest pro-British party.

April 2005 - Sinn Fein calls on the IRA to end its armed campaign after a series of high-profile crimes are linked to the group.

July - The IRA says it ordered its guerrillas to dump all arms and pursue their goal of a united Ireland through purely peaceful means.

October 2006 - British Prime Minister Tony Blair and Irish Prime Minister Bertie Ahern launch talks with Northern Ireland's parties and put forward a plan for reviving self rule by a March 26 deadline.

January 2007 - Sinn Fein's mostly Catholic membership votes overwhelmingly to back the Protestant-dominated Police Service of Northern Ireland after decades of opposition and mistrust, fulfilling a key condition for the revival of the assembly.

March - Both the DUP and Sinn Fein increase their shares of the vote in new assembly elections.

-- DUP leader Ian Paisley and Sinn Fein leader Gerry Adams hold their first face-to-face meeting.

May - A new power-sharing assembly government is launched on May 8, with Paisley as first minister and Sinn Fein's Martin McGuinness as his deputy.

June 5, 2008 - Peter Robinson takes over as first minister, succeeding Ian Paisley who retired as DUP leader on May 31.

September 3 - The Independent Monitoring Commission (IMC) says the IRA's ruling Army Council is no longer operational and the guerrilla group does not pose a threat to peace.

March 7, 2009 - Gunmen kill two British soldiers and wound four other people at the Massereene base near Antrim. The Real IRA, a splinter group of the IRA, later claims responsibility. Two days later a policeman is shot dead in Craigavon, the first policeman killed since 1998. The Continuity IRA later claim responsibility for the killing.

June 27 - The UVF (Ulster Volunteer Force) says it has completed the decommissioning of its weapons and the UDA (Ulster Defence Association) says it has also started the process. Both are pro-British paramilitary forces.

September 8 - The UDA and a breakaway faction say they have told the Commission on Decommissioning that they were committed to destroying their arsenal.

-- Police make safe a bomb containing 600 lb (270 kg) of homemade explosives.

Oct 10 - The Irish National Liberation Army (INLA) says it will end its violent activities.

Oct 12 - U.S. Secretary of State Hillary Clinton addresses Stormont and holds talks with leaders in Belfast.

Oct 21 - British Prime Minister Gordon Brown says he has agreed funding for the devolution of policing and justice in Northern Ireland, an issue that had strained the province's power-sharing administration. Brown reached the deal at talks with Robinson and McGuinness.

January 8, 2010 - Republican militants seriously injure a police officer when they explode a bomb under his car, in the latest of increasingly frequent attacks.

Jan 11 - Robinson asks party colleague Arlene Foster to temporarily stand in as head of the province's executive, after calls to resign over disclosures about his family's finances.

Jan 25 - The prime ministers of Britain and Ireland, Gordon Brown and Brian Cowen, fly to Belfast for talks to try to overcome a dispute over the transfer of police and justice powers from London to Belfast.