They took to Reddit in their millions in the hope of pinpointing the suspect or suspects behind the Boston Marathon bombings, which killed two women and a young boy, and injured a further 264. But in the days after the 2013 attack, the users of the subreddit, Find Boston Bombers, hurled false accusations at countless spectators who had been wearing backpacks at the high-profile event. Their claims - based on the analysis of photos and videos of the marathon - even led to 22-year-old Sunil Tripathi, a Brown University student who was missing, being wrongly identified as the bomber. Now, the moderator of the subreddit, Chris Ryves, has told of his regrets about the thread - which he says nearly became 'its own beast' in the wake of the April 15 bombings - in a new documentary. SCROLL DOWN FOR VIDEO . Regret: The moderator of the Reddit thread, Find Boston Bombers, Chris Ryves (pictured), has told of his regrets about the subreddit - which he set up after the Boston Marathon Bombings - in a new documentary . Theories: Millions of users took to Ryves's thread on the day of the bombings, and following days, highlighting spectators whom they believed looked suspicious based on their demographics and whether they had been wearing a backpack at the event. Above, a still from a trailer for the documentary, released on Monday . Detailed analysis: 'They were just analyzing the same pictures, like it was a Where's Waldo? game,' one journalist says in the trailer. Another adds: 'They would draw a circle around the guy or around the backpack' Wrong man: The Redditors' accusations even led to 22-year-old Sunil Tripathi (left), a Brown University student who was missing, being wrongly identified as the bomber. Right, Dzhokhar Tsarnaev was actually responsible . In the documentary, The Thread, which will be released on iTunes on Monday, Ryves explains how Redditors took it upon themselves to theorize about the suspect/suspects' identities on his thread. These theories, which may have appeared harmless at first, then spread into the public domain, sparking the widespread rumor that Tripathi was behind the homemade pressure-cooker bombs. 'People like to make theories,' Ryves says in a trailer for the documentary, explaining how he had initially set several ground rules - such as 'No Racism' - for the thread in a bid to ensure fairness. However, as a staggering three million users took to the subreddit to join in the hunt for the killer or killers, he Ryves soon lost control of it. 'It became almost its own beast', he admits in the film. The documentary, which was directed by Greg Barker and executive produced by Jonathan Chinn and Simon Chinn, looks at impact that amateur social media writers are  having on journalism. In particular, it focus on the Internet frenzy in the wake of the Boston Marathon bombings, which Dzhokhar Tsarnaev was this week found guilty of carrying out by a Boston, Massachusetts, jury. Explosion: In the documentary, The Thread, which will be released on iTunes on Monday, Ryves explains how Redditors took it upon themselves to theorize about the bomber/bombers' identities on his subreddit . Identification: 'People like to make theories,' Ryves says in a trailer for the documentary, explaining how he had initially set several ground rules - such as 'no racism' - for the thread. Above, a still from the trailer . Lost control: However, as a staggering three million users took to the subreddit to join in the hunt for the killer or killers, he Ryves soon lost control of the subreddit. 'It became almost its own beast', he says in the film . Comparison: One person in the film (pictured) describes users' analysis as akin to a 'Where's Waldo? game' In the hours after the deadly attack, Reddit users posted images and videos of crowds of spectators at the marathon on Find Boston Bombers, which had been set up by Ryves, known as 'oops777'. 'You look up ‘unlikely journalist’ in the dictionary and there’s this guy,' Jonathan Chinn told Boston.com. 'This guy who had no journalistic background ... was at the hub of all of it.' But despite his lack of journalism, Ryves certainly had an impact. Millions of users took to his thread, highlighting spectators whom they believed looked suspicious based on their race, facial expressions and gaze - and accusing them of being the bomber. 'They were just analyzing the same pictures, like it was a Where's Waldo? game,' one journalist says in the trailer. Another adds: 'They would draw a circle around the guy or around the backpack.' Guilty: A sketch shows Dzhokhar Tsarnaev (second left) and his defense team are seen as the guilty verdicts on all charges against him were read on Wednesday. The jury will now decide if he gets the death penalty . Impact: In the hours after the attack, Reddit users posted images and videos of crowds of spectators at the marathon on Find Boston Bombers, which had been set up by Ryves. Above, another still from the film trailer . Tragic: After Tripathi (pictured, left, with two relatives) was wrongly identified by Reddit commentators (the student was, in fact, found dead in a Rhode Island river on April 23), an apology was issued to his family . And one says: 'Instead of going to police with their tips, people were going on Reddit.' The theories only stopped when Tsarnaev and his brother, Tamerlan, were tracked down by police on April 19. After Tripathi was wrongly identified by Reddit commentators (the student was, in fact, found dead in a  Rhode Island river on April 23 after committing suicide), an apology was issued to his family. The apology, written by the then-unidentified moderator of Find Boston Bombers, told Tripathi's relatives that the thread was 'truly sorry' for pinpointing the victim, who went missing on March 16. It read: 'I'd like to extend the deepest apologies to the family of Sunil Tripathi for any part we may have had in relaying what has turned out to be faulty information. We cannot begin to know what you're going through and for that we are truly sorry. 'Several users, twitter users, and other sources had heard him identified as the suspect and believed it to be confirmed. We were mistaken.' Plot: The Reddit users' theories only stopped when Tsarnaev (right) and his brother, Tamerlan (left), were tracked down by police on April 19. Lawyers for Tsarnaev blamed the attacks on his older brother in court . Heroic: Jeff Bauman can be seen running at the side of Jeff Bauman, who lost both legs in the 2013 explosion . Chilling: Martin Richard, who was killed in the bombings, is seen (front circle) just meters away from Tsarnaev (back circle) on April 15. Seconds later, one of two bombs exploded, piercing his body with shrapnel . Erik Martin, the general manager of Reddit, also sent out an email 'to apologize personally for... some of the people on our site's role in the spreading of this false idea about Sunny.' Speaking to Boston.com, Jonathan Chinn explained that although citizen journalism is important to 'the way news is gathered and broadcast', there are issues with it because it moves 'so quickly'. The Thread features interviews with journalists from established media outlets, as well as several Reddit users who were involved in the hunt for justice following the deadly twin bombings in 2013. It will also be available to view and download on other major digital platforms on Monday. Victims: Krystle Campbell (left) and Martin Richard (right) were killed in the blast at the marathon finish line . Killed: Lingzi Lu, 23, also died at the marathon, while MIT Police Officer Sean Collier, right, was later shot dead .
Chris Ryves set up Find Boston Bombers thread after the 2013 bombings .
Within hours, millions of users had taken to subreddit to identify bomber .
They analysed photos and videos of spectators at marathon on April 15 .
Slung false accusations at those wearing backpacks or acting strangely .
Claims led to Sunil Tripathi, 22, being wrongly identified as the suspect .
Frenzy only halted after Dzhokhar and Tamerlan Tsarnaev were named .
Now, Ryves has told of regrets about Reddit thread in new documentary .
In film, The Thread, he says the subreddit 'became almost its own beast'