A soldier in Afghanistan learned about the death of Osama bin Laden on Facebook. A TV producer got a tip from comedian Kathy Griffin on Twitter. A blues musician received an email alert from The New York Times. And a woman found out as she absently scrolled through the Internet on her smartphone while walking her dog.

In an illustration of how the information world has changed, many people learned through media formats or devices that weren’t available a decade ago that the mastermind of the September 11, 2001, terrorist attacks had been killed.

“It just kind of spread like wildfire online,” said Stephen Vujevich, a student at Immaculata University in Pennsylvania. “It’s amazing to see how social media played a part in it.”

Mr. Vujevica was at his girlfriend’s house and both were on their laptops, when she said that many of her friends had updated their Facebook status to note bin Laden’s death in Pakistan. He went to Google News to find out that President Barack Obama had scheduled an address to the nation. He searched other sites to get news and credited Twitter with giving him the most immediate information.

Jaime Aguilar, a Denver musician, was at a friend’s house watching cable TV channel HBO when he saw the news alert on his smartphone.

A soldier who identified himself only as Carlos from Queens called New York sports radio station WFAN on Monday to note that he and his buddies in Afghanistan learned the news not from commanding officers, but from Facebook. Angie Scharnhorst of Kansas had an early morning plane flight and if she wasn’t carrying her smartphone while walking her dog at 2 a.m., she said she probably wouldn’t have heard the news until later in the day on Monday.

Ashlee Edwards, a content producer for the CBS affiliate WBTW-TV in Myrtle Beach, South Carolina, was watching The Tudors with a friend when she saw Griffin’s tweet urging her to “turn on CNN now” because the President was about to make an announcement.

Abroad, the mediums of choice were much the same. Perhaps most prominently, one Twitter user told the story before the world knew what was happening — he lives near the compound in Pakistan where bin Laden was killed and became, in his words, “the guy who liveblogged the Osama raid without knowing it.”

Sohaib Athar, 33, is a computer programmer who was startled by a helicopter clattering in the early hours on Monday. He tweeted about it, and soon the sole helicopter multiplied into several and gunfire and explosions rocked the air above the town. Mr. Athar’s tweets quickly garnered tens of thousands of followers as he apparently became the first in the world to describe the U.S. operation to kill one of the world’s most wanted terrorists.

Elsewhere, Shari Mai of Middlesex, England, said through Facebook that she heard the news via the Financial Times. Marina Ch of Moscow learned it through Facebook and The Associated Press. Monique Taylor, an Australian, said she was in London and the story was all over Facebook.

In Washington, it was before 10 p.m. EDT (7.30 a.m. IST, Monday) on Sunday that many Washington-based reporters were told to get to work because the President would speak. They were not told why.

At 10.25 p.m. EDT (7.55 a.m. IST, Monday), Keith Urbahn, the chief of staff for former Defence Secretary Donald Rumsfeld tweeted: “So I’m told by a reputable person that they have killed Osama bin Laden. Hot damn.”

The word spread quickly, even as Mr. Urbahn subsequently tweeted that he “didn’t know if it’s true, but let’s pray it is.”

Mainstream news organisations began reporting that bin Laden was dead about 15 or 20 minutes later. Some, such as CNN and NBC, were tentative at first. Others, including ABC, were more definitive. Fox News Channel was joyful.

“This is the greatest night of my career,” said Fox’s Geraldo Rivera. “The bum is dead, the savage who hurt us so grievously. I am so blessed, so privileged to be at my desk at this moment.”

Power of Twitter

The speed of social media struck some as an epochal moment in news coverage. “If anyone isn’t a believer in Twitter as an amazingly powerful news vehicle, last night should convert you,” tweeted Chris Cillizza of the Washington Post’s political website The Fix.

Twitter said that it saw its highest sustained rate of tweets. There was an average of 3,440 tweets-per-second from 10.45 p.m. EST to 12.30 a.m. EST (8.15 a.m. to 10 a.m. IST, Monday), according to the site. At 11 p.m. EST (8.30 a.m. IST, Monday), there were 5,106 tweets-per-second.

Internet traffic surged above normal Sunday night usage. Akamail Technologies, which delivers about 20 per cent of the world’s Internet traffic, said that global page views for the roughly 100 news portals for which it delivers content peaked at more than 4.1 million page views around 11 p.m. EDT. CNN, Fox News Channel and MSNBC had nearly 15 million viewers between 11 p.m. and midnight on Sunday when Mr. Obama spoke, led by CNN’s 7.8 million. That time on a typical Sunday, the three networks are pulling in 1.7 million viewers, according to the Nielsen.

There was a rush for information on mainstream online news sites, and sometimes it caused problems; The New York Times website was inaccessible for about 30 minutes shortly after the news broke due to the volume of traffic. ABC News said its digital properties had their busiest hour in their history on Sunday night. MSNBC said its site had delivered 1.73 million streams of Mr. Obama’s speech on Sunday night.

At CNN, which reported at 10 p.m. EDT (7.30 a.m. IST, Monday) that Mr. Obama would speak, it was another 45 minutes until the speech was connected to bin Laden, even as Wolf Blitzer provided some cryptic teases: “I have my suspicion on what the President is going to announce. Probably something we’ve been looking forward to, at least from a U.S. perspective, for quite a while.” CNN’s John King eventually reported the news.

Mr. Blitzer conceded on Monday that he had a pretty good idea what the news would be when sources assured him that the President’s news was not about Libya.

“I didn’t report it because you don’t report something like that based on a suspicion, based on a hunch, based on your journalistic gut instinct,” Mr. Blitzer said. “You’ve got to get confirmation. And you can’t just confirm from one source. You need at least two really excellent sources.”