Videos and images from eyewitnesses shared on social media are often picked-up by news organisations to illustrate stories, or become a story themselves.
But if this user-generated content (UGC) is not what it claims to be, what should news outlets look out for when coming across such videos or photos?
Earlier this month, a video appearing to show a Syrian "hero boy" rescuing a girl from gunfire was uploaded to YouTube.
It attracted the attention of media organisations including the BBC, where the UGC Hub assessed the video and found it to be too suspicious to share.
BBC Trending assess the veracity of the 'Syria Hero Boy video'
The video turned out to be a Norwegian film created to raise awareness about the daily reality of children in conflict zones.
"In this case, as we now know, the people who made it went to some meticulous lengths to make it as realistic as possible," BBC News social media editor Chris Hamilton told Journalism.co.uk.
But what seemed strange in the first place?
Hamilton said the starting point for UGC verification is to talk to the source, but this may not always be possible when dealing with materials coming out of conflict zones.
Too good to be true?
Instead, one of the first questions journalists should ask themselves when dealing with UGC is if the video or photo is too good to be true, he said.
"Am I just falling into the trap that this is an amazing picture, this is going to get so much traffic, it's going to draw us so much attention?
"That test is always a good alarm bell."
He highlighted pictures that appeared online in the aftermath of Hurricane Sandy, showing sharks swimming in flood water in what used to be a suburban street.
Hamilton said it could have been a "fantastic illustration of the story", showing the impact of the storm on communities, but it turned out to be a hoax.
Pay attention to the technical side
When dealing with user-generated videos, assessing the audio is an important part of the verification process.
In the case of the "Syrian hero boy" video, there were reasons to believe some of the voices were added on later.
"The quality of the voices didn't quite seem to stack up with the environment in which it was apparently filmed, so there was a suspicion they may have been dubbed on," said Hamilton.If this was taken yesterday in Damascus, does the weather match up?Chris Hamilton, BBC News
He told Journalism.co.uk listening to audio for any features that might not make sense has been helpful in identifying videos likely to be fake.
In the early days of the Syrian conflict, a video which appeared to show a man being buried alive surfaced online.
Hamilton said the BBC collaborated with other media organisations including social media newswire Storyful to verify the footage.
"Collectively we came to the view that it was suspicious and again it was around the audio," he said.
In this case, the voices could be heard at the same volume despite people being positioned at various distances from the camera.
Details don't match up
Hamilton said journalists should "really look" at UGC for any inconsistencies or elements that could not be at the scene if the video was true.
"You can check weather reports, so if this was taken yesterday in Damascus, does the weather match up?
"If it was taken in the morning, do the shadows match with the direction of the sun or is it actually taken in the evening?" he said.
Doing reverse image searches, using tools such as TinEye or Google Search by Image, are also a good way to "debunk images of news events where people either wittingly or unwittingly shared an old image".
Hamilton also explained the BBC does not share videos because they are "doing the rounds" online.
"I think that's a bit of a slippery slope and something that we'd be very wary of getting into," he said.
BBC Academy also published a verification checklist outlining helpful tips and tools for journalists dealing with UGC, and the European Journalism Centre's Verification Handbook is a rich source of tools and tips as well.
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