After four bombs rocked the city, killing at least 37 and wounding more than 700, Flickr members started to pool photos from the event that include pictures of people standing behind blocked streets, armed men boating toward Parliament, and a chilling photo of people evacuating a train via a dark subway tunnel.
A total of about 300 photos have been contributed, and certain photos have been viewed up to 6,000 times.
One Flickr picture of a London-based mosque, once suspected of being an al-Qaida recruitment center, showed the building draped with a sign claiming its "new beginning."
Underneath the photo, someone wrote, "Its neither the fault or sole responsibility of Muslims or Islam, but its hard not to think, when passing the Finsbury Park mosque, of the extremists who were based here up to a year ago."
This growing collection of photos comes from a specific user-created group that allows any Flickr member to contribute pictures.
Also, users can search specific tags—the most popular tags listed today are "blast," "explosion" and "London"—which pools photos associated with those key words from across the site.
Other sites with similar photo-sharing capabilities have seen the same activity.
Photo communications site Buzznet.com showed a few pictures taken of the aftermath, one including a picture of the double-decker bus that was attacked.
Underneath each photo on this site, people have been posting their experiences and condolences.
One entry underneath a photo said, "Looking at these posts… I wonder… where are my friends?"
Another picture posted on MoblogUK of a man covering his face while exiting a stalled train has been viewed 20,819 times, and more pictures are starting to surface on other similar sites.
Flickr co-founder Caterina Fake said that the site has been experiencing an increase in traffic after the London bombing, but nothing that the company isnt ready to handle.
Ironically, on Wednesday night, she said they moved their data center to a "bigger, better, faster" facility in Dallas as part of its recent acquisition by Yahoo Inc.
As for the photo sharing based on the London bombings, Fake said they saw similar surges in activity after the December 2004 tsunami and after the Jakarta embassy bombings in September 2004.
"These kinds of surges in activity we plan in advance for," she said. "We know, for instance, that after holidays, people will be loading a lot of photographs; after long weekends people will be uploading a lot of photographs."
After a large global event, though, she says most of the traffic comes from viewers rather than people uploading photo.
"Its just like Paretos rule—that 20 percent of people will be contributing and 80 percent of the rest will be watching," Fake said.
Photo sharing and citizen journalists have had such an impact that the big news organizations are jumping in on the action as well. The London Times has urged readers to send in their personal photos by posting a link at the top of its site.