NEW DELHI — When gunmen started spraying Mumbai with bullets and seizing the city’s landmarks, countless people around the globe turned not to the television or the radio for news, but to each other.

Blogs and social networking sites such as Twitter and Flickr buzzed with eyewitness accounts from India’s financial capital, providing some of the first photos of the besieged targets and serving as a forum for pleas for updates on friends and family.

Photos posted on Flickr just 90 minutes after the attacks had been viewed at least 110,000 times by Sunday.

Twitter users, who simply tagged their comments “mumbai,” traded information at a rate of 50-100 posts a minute in messages that were sometimes wrong, often fragmented, but always instant.

The lightning-quick updates of the attacks that killed 174 people read like a sketchy but urgent blow-by-blow account of the siege, providing further evidence of a sea change in how people gather their information in an increasingly Internet-savvy world.

“‘Emergency’ can some one check if there bomb blast of some shootout in oberoi hotel of anywhere in Mumbai ? I am at inox inside,” a user named Puneet wrote on Twitter, a popular “microblogging” Web site, shortly after the violence began.

“I just heard what sounded like a bomb blast! I hope I am wrong,” krazyfrog, a user in Mumbai, wrote soon after.

“People stay where you are. We’re under attack,” wrote Whizzkidd, also in the city.

The dramatic siege, which targeted some of the city’s most famous landmarks, threw the user-generated corner of the Internet into high gear.

A Google map of the targets was created hours after the violence began and had received 375,000 hits at last glance. A Wikipedia page was created for the attacks and has been updated thousands of times. Blogs such as Mumbai Heros were created to honor the victims.

Vinukumar Ranganathan, 27, posted some of the first photos of the attacks. After hearing the initial blasts Wednesday night, he grabbed his camera and rushed outside his apartment near many of the targets. He found a chaotic scene of destroyed cars, buildings with blown out windows, and pools of blood spreading in the street and finally arrived at the besieged headquarters of an ultra-Orthodox Jewish center ahead most of the local and international press.

An hour and a half later — while much of the world was still struggling to understand what was unfolding — Ranganathan announced on Twitter that he had posted 112 photos on Flickr, a popular photo-sharing Web site.

Over the next three days, he ventured out into the streets several times, photographing and posting what he saw. The pictures are blurry and raw, but, taken together, provide a compelling portrait of this week’s chaos and carnage.

Some bloggers posted firsthand accounts of the attacks on their own sites.

Sonia Faleiro “ate stir fry and drank campari” at a boutique hotel near the landmark Taj Mahal hotel just before the violence began.

“We stepped out of the hotel and bullets rang in the air, people screamed, a tidal wave raced down the street and the security guard said ‘Inside! Madam, Inside NOW!”’ she wrote. “We thought then it was a gang war, and it would end soon.”

During the attacks Twitter became the village square for the online world, and the posts served as all things at once, such as public service announcements about where to donate blood and news ticker updates of death tolls.