All times Eastern
Chronology of some key events in U.S. relations with Islamic groups and with Osama bin Laden before Sept. 11, 2001, and of the Sept. 11 attacks and aftermath:
Feb. 26, 1993 _ Bomb explodes in garage under World Trade Center, killing six and injuring more than 1,000. Group of Islamic extremists later convicted.
Nov. 13, 1995 _ Seven people, including five Americans, killed when two bombs explode at U.S.-Saudi military facility in Riyadh, Saudi Arabia. Osama bin Laden blamed for attack.
Sept. 27, 1996 _ Taliban, suspected of giving refuge to bin Laden, completes takeover of Kabul, Afghanistan.
June 25, 1996 _ Bin Laden followers detonate bomb at U.S. military base near Dhahran, Saudi Arabia, killing 19 American soldiers and wounding hundreds of Americans and Saudi Arabians.
Aug. 7, 1998 _ U.S. embassies in Nairobi, Kenya, and Dar es Salaam, Tanzania, bombed, killing more than 250 people, including 12 Americans, and injuring 5,000. In retaliation, United States launches airstrikes against suspected terrorist camps in Sudan and Afghanistan.
Aug. 28, 1998 _ FBI accuses bin Laden of having declared "jihad," or holy war, against United States. Complaint also alleges bin Laden founded al-Qaida that year to promote Islamic fundamentalism and force non-Muslims out of Muslim countries.
November 4, 1998 _ Bin Laden charged with ordering embassy bombings.
Oct. 12, 2000 _ Suicide bombers in Yemen attack U.S. Navy destroyer USS Cole, killing 17 sailors. Officials suspect bin Laden involvement.
Jan. 15, 2001 _ U.N. imposes new economic sanctions against Taliban for refusing to turn over bin Laden for trial.
Sept. 11, 2001:
8 a.m. _ American Airlines Flight 11, Boeing 767 with 92 people on board, takes off from Boston's Logan International Airport for Los Angeles.
8:14 a.m. _ United Air Lines Flight 175, Boeing 767 with 65 people on board, takes off from Boston's Logan airport for Los Angeles.
8:21 a.m. _ American Airlines Flight 77, Boeing 757 with 64 people on board, takes off from Washington Dulles International Airport for Los Angeles.
8:40 a.m. _ Federal Aviation Administration notifies North American Aerospace Defense Command's Northeast Air Defense Sector about suspected hijacking of American Flight 11.
8:41 a.m. _ United Air Lines Flight 93, Boeing 757 with 44 people on board, takes off from Newark International Airport for San Francisco.
8:43 a.m. _ FAA notifies NORAD's Northeast Air Defense Sector about suspected hijacking of United Flight 175.
8:46 a.m. _ American Flight 11 crashes into north tower of World Trade Center.
9:03 a.m. _ United Flight 175 crashes into south tower of World Trade Center.
9:08 a.m. _ FAA bans all takeoffs nationwide for flights going to or through New York Center airspace.
9:21 a.m. _ All bridges and tunnels into Manhattan closed.
9:24 a.m. _ FAA notifies NORAD's Northeast Air Defense Sector about suspected hijacking of American Flight 77.
9:26 a.m. _ FAA bans takeoffs of all civilian aircraft.
9:31 a.m. _ In Sarasota, Fla., President Bush calls crashes an "apparent terrorist attack on our country."
9:40 a.m. (approx.) _ American Flight 77 crashes into Pentagon.
9:45 a.m. _ FAA orders all aircraft to land at nearest airport as soon as practical. More than 4,500 aircraft in air at the time.
9:48 a.m. _ U.S. Capitol and White House's West Wing evacuated.
9:59 a.m. _ South tower of World Trade Center collapses.
10:07 a.m. (approx.) _ United Flight 93 crashes in Pennsylvania field.
10:28 a.m. _ North tower of World Trade Center collapses.
11 a.m. _ New York mayor orders evacuation of lower Manhattan.
1:04 p.m. _ From Barksdale Air Force base in Louisiana, Bush announces U.S. military on high-alert worldwide.
2:51 p.m. _ Navy dispatches missile destroyers to New York, Washington.
3:07 p.m. _ Bush arrives at U.S. Strategic Command at Offutt Air Force Base in Nebraska.
5:25 p.m. _ Empty 47-story Seven World Trade Center collapses.
7 p.m. _ Bush arrives at White House.
8:30 p.m. _ Bush addresses nation and vows to "find those responsible and bring them to justice."
_ Sept. 12: Bush labels attacks "acts of war," asks Congress to devote $20 billion to recovery, allies to join war on terrorism. NATO declares terrorism an attack on all 19 member states.
_ Sept. 13: Secretary of State Colin Powell identifies bin Laden as prime suspect. Limited commercial flights resume. National Football League, major-league baseball call off weekend games.
_ Sept. 14: Justice Department names 19 suspects in attacks; intelligence sources link them directly to bin Laden. Bush gives military authority to call up 50,000 reservists. Afghanistan's ruling Taliban warns of revenge if United States attacks. Bush leads nation in prayer at National Cathedral.
_ Sept. 15: Pakistan agrees to U.S. demands for possible attack on neighboring Afghanistan.
_ Sept. 16: Bush pledges "crusade" to "rid the world of evil-doers."
_ Sept. 17: Wall Street trading resumes, ending stock market's longest shutdown since the Depression. Dow loses 684.81 points, its worst-ever one-day point drop.
_ Sept. 18: Taliban leaders call on Muslims to wage holy war on United States if it attacks.
_ Sept. 19: Pentagon orders combat aircraft to Persian Gulf bases. American and United airlines announce 40,000 layoffs.
_ Sept. 20: Bush announces new cabinet-level Office of Homeland Security, to be led by Pennsylvania Gov. Tom Ridge.
_ Sept. 24: Bush orders U.S. financial institutions to freeze assets of 27 groups and individuals suspected of supporting terrorists.
_ Sept. 25: Saudi Arabia cuts ties with Taliban government.
_ Sept. 27: Bush announces plan to bolster airline security, including expanded use of federal marshals on airliners.
_ Sept. 28: U.N. Security Council approves U.S.-sponsored resolution demanding all nations take sweeping action against terrorism.
_ Oct. 5: Tabloid photo editor Robert Stevens dies of anthrax in Florida, in nation's first known case of inhalation version of disease since 1976; a total of five people eventually die from anthrax infections. Army dispatches 1,000 soldiers to Uzbekistan, which borders Afghanistan.
_ Oct. 7: First airstrikes launched in Afghanistan; targets include capital of Kabul, bin Laden training camps and Taliban bases. Bin Laden, in videotaped message, praises God for Sept. 11 attacks and swears America will never "dream of security" until "the infidels' armies leave the land of Muhammad."
_ Oct. 10: Air Force sergeant killed in heavy-equipment accident in northern Arabian peninsula, becoming first death in campaign.
_ Oct. 11: U.S. troops, aircraft deployed in Pakistan despite Islamic protests.
_ Oct. 14: Bush rejects Taliban offer to discuss turning over bin Laden if U.S. ends bombing in Afghanistan.
_ Oct. 15: Officials announce anthrax spores found in letter to Senate Majority Leader Tom Daschle.
_ Oct. 16: United States, Pakistan announce support for multi-ethnic, democratically elected government in Afghanistan.
_ Oct. 26: Bush signs anti-terrorism bill giving police unprecedented ability to search, seize, detain and eavesdrop in pursuit of possible terrorists. Officials announce discovery of trace anthrax at State Department and CIA buildings.
_ Oct. 28: Thousands of relatives of World Trade Center victims gather at site for first official memorial.
_ Oct. 29: Bush announces terrorist-tracking task force to keep foreigners who are planning attacks from entering America.
_ Oct. 31: American Red Cross stops accepting donations to terrorism victims fund after raising more than a half-billion dollars.
_ Nov. 7: Federal agents raid U.S. businesses suspected of helping funnel millions of dollars to bin Laden's network. Bush asks at least nine countries to freeze assets that aid bin Laden and al-Qaida.
_ Nov. 9: Taliban abandon strategic northern Afghan city of Mazar-e-Sharif, allowing Northern Alliance to take control.
_ Nov. 13: Northern Alliance troops enter Kabul after flight of Taliban forces that had ousted them in 1996.
_ Nov. 19: Bush signs law to hire 28,000 federal workers to screen passengers and baggage at major airports.
_ Nov. 25: First wave of Marines lands near Taliban stronghold of Kandahar. CIA officer Johnny Spann killed by rioting prisoners at Mazar-e-Sharif, in first death of American in action in Afghanistan.
_ Dec. 1: Northern Alliance forces turn over to U.S. custody John Walker Lindh, American who fought with the Taliban.
_ Dec. 5: Three American soldiers killed by "smart" bomb dropped by B-52 near Kandahar.
_ Dec. 7: Taliban forces begin surrendering in Kandahar.
_ Dec. 10: Marines move back to American embassy in Kabul after 12-year absence.
_ Dec. 11: First criminal charges in Sept. 11 attacks brought against Zacarias Moussaoui.
_ Dec. 15: Last piece of trade center facade pulled down.
_ Dec. 22: British citizen Richard Reid allegedly tries to blow up Miami-bound jet using bomb hidden in shoe. Karzai and his transitional government sworn in.
_ Dec. 28: Bush signals bin Laden may never be caught, saying "Our objective is more than bin Laden."
_ Jan. 4: U.S. military loses first member to hostile action when Army Special Forces sergeant killed near Khost, Afghanistan.
_ Jan. 9: Seven Marines killed when tanker plane crashes into mountain in Pakistan.
_ Feb. 13: Lindh pleads innocent to a 10-count federal indictment charging him with aiding bin Laden's terrorist network.
_ Feb. 17: Federal government assumes control of security checkpoints at nation's 429 commercial airports.
_March 18: U.S. commanders declare end of Operation Anaconda, the largest U.S.-led ground operation in Afghan campaign, but many Taliban and al-Qaida fighters slip through dragnet and seek refuge in Pakistan.
_ May 28: Last standing steel beam from trade center cut down during ceremony for ground zero workers.
_ June 19: Loya Jirga, Afghanistan's Grand Council, completes work on new government.
_ July 1: U.S. air raid in Uruzgan province kills 46 civilians, including 25 at a wedding party, according to Afghan government. U.S. military says forces came under anti-aircraft fire and acknowledges civilian casualties.
_ July 15: Lindh pleads guilty to supplying services to Taliban and carrying explosives during commission of a felony and agrees to cooperate with terrorism investigations.
_ July 15: Ceremony ends 10 months of sifting through trade center ruins.
_ Aug. 15: More than 600 family members of Sept. 11 victims file trillion-dollar federal lawsuit against Saudi officials and institutions.
_ Aug. 17: Moussaoui trial delayed until Jan. 6, 2003.
Compiled by Associated Press researchers Justin Glanville, Julie Reed, Rhonda Shafner.