Twitter slapped a warning label on an election-night tweet from President Donald Trump, for “making a potentially misleading claim about an election.” In the tweet, Trump claimed that “they are trying to STEAL the Election,” and that “Votes cannot be cast after the Polls are closed.”

The label appears in place of the tweet in users’ timelines, though they can still click through to view it. “Some or all of the content shared in this Tweet is disputed and might be misleading about an election or other civic process,” the notice says. Users are also blocked from retweeting, though they can still share it with a Quote Tweet.

In a statement shared shortly after the label appeared, Twitter confirmed the tweet had broken its rules around “making a potentially misleading claim about an election.” The company previously said it would label tweets that break its rules around declaring victory prematurely, or making false claims about the election or ballot-counting process.

On Facebook, where Trump posted the same message, Facebook applied a more vague label that says “final results may be different from initial vote counts, as ballot counting will continue for days or weeks.” The social network also labeled another Trump post, which said “I will be making a statement tonight. A big WIN!” That post bears a similar notice that “ballots are still being counted,” and a winner has not been projected. Twitter has so far opted to not label that tweet.

Trump’s claims were among the first major test of social media platform’s election-night policies, which both Facebook and Twitter have spent months preparing for. Earlier in the night, Twitter labeled a tweet from Trump’s campaign about the results in South Carolina. Both companies previously said they would not allow either presidential candidate to declare victory before results are clear, and that they would rely on state election officials and national media organizations to make those calls.