Twitter has used its new "manipulated media" tag for the first time on an edited video of a speech by Joe Biden.
The tag, introduced on 5 March, tells readers when a picture or video has been "significantly altered or fabricated".
The footage of Mr Biden, posted by Dan Scavino, White House director of social media, claimed to show the Democrat calling for people to vote for President Donald Trump, a Republican.
The video was shared by Mr Trump twice.
In the clip, Mr Biden appeared to tell a crowd in Kansas City: "We can only re-elect Donald Trump."
