Obama announces Osama bin Laden killed

Updated at 1:12 a.m. ET

Senior administration officials, who asked not to be identified because of the sensitivity of the information, gave a tick tock of events that led to the killing of Osama bin Laden:

On June 2, 2009: President Obama signed a memo to CIA Director Leon Panetta stating "in order to ensure that we have expanded every effort, I direct you to provide me within 30 days a detailed operation plan for locating and bringing to justice Osama bin Laden."

Obama convened at least nine meetings with his national security team and the principals met formally an additional five times, plus their deputies met seven times leading up to the operation that killed bin Laden. Obama was actively involved in reviewing all facets of the operation.

8:20 a.m. ET, April 29: Obama decided to go ahead with the operation that eventually led to bin Laden's death before he left on a trip to Alabama to inspect tornado damage.

The events of Sunday, May 1 are as follows:

Staff worked all day on the operations.

2 p.m. ET: Obama met with the principals of his national security team to review final preparations.

3:32 p.m. ET: Obama returned to the White House Situation Room for another briefing on the matter.

3:50 p.m. ET: Obama first learns that bin Laden was tentatively identified.

7:01 p.m. ET: Obama learns that there's a "high probability" that bin Laden was the "high value target" inside a heavily barricaded compound in Pakistan.

8:30 p.m. ET: Obama received more briefings.

Updated at 12:53 a.m. ET

Earlier, President Obama made the dramatic announcement that U.S. forces killed Osama bin Laden, the mastermind behind the terrorism attacks of Sept. 11, 2001.

Obama ordered the operation on bin Laden after receiving intelligence information.

The Associated Press, citing unnamed senior administration officials, reports that bin Laden was found inside a custom-built compound with two security gates. For undisclosed reasons, it became clear the hideout was bin Laden's.

The AP says there is no word on the whereabouts of Ayman al-Zawahri, bin Laden's second-in-command.

Updated at 12:45 a.m. ET

The State Department has put U.S. embassies on alert, warning of the increased possibility for anti-American violence after the death of Osama bin Laden.

Earlier, President Obama told the nation that bin Laden has been killed by U.S. forces in Pakistan.

From the travel alert:

"Given the uncertainty and volatility of the current situation, U.S. citizens in areas where recent events could cause anti-American violence are strongly urged to limit their travel outside of their homes and hotels and avoid mass gatherings and demonstrations."

The State Department said U.S. embassy operations will continue "to the extent possible under the constraints of any evolving security situation." Some embassies and consulates may close temporarily or suspend services.

Updated at 11:44 p.m. ET

Obama is finishing up and addressing the families who lost loved ones on 9/11:

"We have never forgotten your loss, nor wavered in our commitment to see that we do whatever it takes to prevent another attack on our shores."

He added: "Today's achievement is a testament to the greatness of our country and the determination of the American people."

"America can do whatever we set our mind to. ... Let us remember that we can do these things ... because of who we are: one nation, under God, indivisible, with liberty and justice for all."

Updated at 11:43 p.m. ET

"Justice has been done," Obama said.

Updated at 11:42 p.m. ET

Obama said this news "should be welcomed by all who believe in peace and human dignity."

He praised the counterterrorism efforts given by Pakistan that helped lead us to bin Laden. After speaking to Pakistan's president, Asif Ali Zardari, Obama said that he and his counterpart believe:

"This is a good and historic day for both of our nations," Obama said.

Updated at 11: 39 p.m. ET

Obama said last week he "determined there was enough intelligence to take action and authorized action."

The president said he ordered a "targeted operation" today in Pakistan.

He said that "after a firefight" U.S. forces "killed bin Laden and took custody of his body."

No Americans were harmed and care was taken to avoid civilian casualties, Obama said.

Updated at 11:38 p.m. ET:

Obama is going over the 10-year hunt for bin Laden. He said he asked the CIA director to make the killing of bin Laden a top priority for the U.S.

Updated at 11:36 p.m. ET

Obama discusses what happened after 9/11: "The American people came together. We offered our neighbors a hand, and we offered the wounded our blood. We reaffirmed our ties to each other, and our love of community and country. On that day, no matter where we came from, what God we prayed to, or what race or ethnicity we were, we were united as one American family."

Updated at 11:35 p.m. ET

President Obama just announced that the U.S. has conducted an operation that killed Osama bin Laden.

"Tonight, I can report to the American people and to the world that the United States has conducted an operation that killed Osama bin Laden, the leader of al-Qaeda, and a terrorist who's responsible for the murder of thousands of innocent men, women, and children."

Updated at 11:30 p.m. ET

Some reaction on reports that Osama bin Laden is dead:

"It's not going to mean the end of the movement because there are still those feeding off the anger. They will take up arms. This movement has grown beyond this man," said James Zogby, president of the Arab American Institute.

"It means a lot," said Carie Lemack, whose mother, Judy Larocque was aboard American Airlines Flight 11. "The man who plotted to kill my mom." Lemack, who was sobbing at the news, said she was contacted by the White House about half an hour before Obama spoke and told to watch. No one told her the subject. She was with her father and sister, celebrating her sister's birthday. "I just want to make sure we focus on the people he murdered," she said. "I don't want this day to be about him."

Our original post begins here:

President Obama will soon announce that Osama bin Laden is dead, according to several news reports.

CNN reports that bin Laden was killed by the U.S. in a mansion outside Islamabad.

A senior U.S. counterterrorism official said bin Laden was killed in a ground operation in Pakistan, not by a Predator drone. The official told the Associated Press it happened last week.

The al-Qaeda figurehead was a mastermind behind the Sept. 11 terrorist attacks on the United States.

The White House said Obama will make a major announcement about national security on Sunday evening.

(Contributing: Megan H. Chan, Mimi Hall, Richard Wolf and Jackie Kucinich)