Twitter shares were down 18% in premarket trading after Elon Musk said in a tweet that a deal for the company was temporarily on hold.
No other details were available.
Twitter’s board accepted Musk’s offer in late April to take the social media giant private at $54.20 per share. Musk, the world’s richest man and the chief executive of Tesla Inc., had said that one of his priorities would be to remove “spam bots” from the platform.
The company had earlier this month estimated that false or spam accounts represented fewer than 5% of its monetizable daily active users during the first quarter.
It also said it faced several risks until the deal with Musk is closed, including whether advertisers would continue to spend on Twitter.
Twitter did not immediately respond to a request for comment.
Reuters contributed to this report.