FBI crime scene investigators photograph evidence after placing a marker on Boylston Street just past Berkeley Street April 17, 2013 in Boston, Massachusetts. - 

Authorities in Boston have flagged video and other images of a possible suspect in the marathon bombings. The Associated Press says there's no identification yet. The U.S. Attorneys' Office and the FBI have been releasing official reports about their investigation, but there's also been amateur sleuthing taking place online at sites like Reddit and 4Chan.

"I think that Reddit is where it pops up the most because [it's] a really popular community that is kind of networked in a way that gives it a lot of visibility," says Adrian Chen, senior writer at the news site Gawker. "But you've [also] got conservative bloggers, you've got people on Twitter, other message boards -- basically wherever anybody is talking on the Internet."

Online postings include time-lapse animations of people seemingly fleeing the bombing scene, and people with backpacks staring unsmiling along the marathon route. Though these efforts may be in good-faith, most, if not all of the people deemed suspicious were most likely not involved.

"This is not an inherently terrible idea to try to sift through some of these pictures to help the authorities, that's if everything goes right," says Will Oremus, a tech writer at Slate. "If everything goes wrong, you've got a lot of people out there who have been identified by their face as possible terrorists and they are totally innocent."

Though Oremus says the idea that “Redditors” could solve a crime isn't too far-fetched.

"A year or two ago, there was a hit and run incident, a photo was posted to Reddit, some gear-head noticed that the headlight belonged to a 1990 Cadillac, he knew the make and model, and they ended up solving the crime," says Oremus. 

To hear more about the implications of a public, crowdsourced manhunt, click on the audio player above.

Correction: The original version of this article misspelled the name of Gawker writer Adrian Chen. The text has been corrected.

Follow David Brancaccio at @DavidBrancaccio