New York:
The terse announcement came just after 9:45 p.m. Sunday from Dan Pfeiffer, the White House communications director. "POTUS to address the nation tonight at 10:30 PM Eastern Time," he wrote on Twitter, sharing the same message that had just been transmitted to the White House press corps.
According to Brian Williams, the "NBC Nightly News" anchor, some journalists received a three-word e-mail that simply read, "Get to work."
The nation's television anchors and newspaper editors did not know, at first, that President Obama would be announcing the death of Osama bin Laden, an extraordinary development in the nearly 10-year-long war against terrorism waged by the United States and its allies. But reporters in Washington suspected almost immediately that the announcement could be about bin Laden.
That speculation was not aired out on television immediately, but it did erupt on Twitter and other social networking sites. Wishful thinking about bin Laden's death ricocheted across the Web -- and then, at 10:25 p.m., while Mr. Obama was writing his speech, one particular tweet seemed to confirm it. Keith Urbahn, the chief of staff for the former defense secretary Donald Rumsfeld, wrote at that time, "So I'm told by a reputable person they have killed Osama Bin Laden. Hot damn."
Mr. Urbahn quickly added, "Don't know if it's true, but let's pray it is." He was credited by many on the Web with breaking the news, though he did not have first-hand confirmation.
Within minutes, anonymous sources at the Pentagon and the White House started to tell reporters the same information. ABC, CBS and NBC interrupted programming across the country at almost the same minute, 10:45 p.m., with the news. "We're hearing absolute jubilation throughout government," the ABC News correspondent Martha Raddatz reported.
Brian Williams, an NBC News anchor, told viewers, "This story started to leak out in the public domain largely when some Congressional staffers started to make phone calls."
The government sources remained anonymous, as The Associated Press said, "in order to speak ahead of the president."
Mr. Obama's address, initially planned for 10:30 p.m., was delayed repeatedly. CNN reported that he was writing the address himself.
By 11 p.m., he still had not spoken, but the news was spreading virally around the world. At that time there were more than a dozen Facebook posts with the word "bin Laden" every single second. The New York Post's Web site blared, "We Got Him!" The Huffington Post front page read, "Dead."
And around the country, Americans gathered around televisions to digest the news. "This ends a chapter in the global war on terrorism which has defined a generation," the NBC correspondent Richard Engel said.
One Twitter user in California said her whole family was watching, including her 9-year-old child. "We're explaining who Osama Bin Laden is," she wrote.
Her child was born several months after the Sept. 11, 2001, terrorist attacks.