Elon Musk took control of Twitter and fired its top executives, US media reported late on Thursday.
Twitter's chief executive Parag Agrawal was among those fired, along with the chief financial officer, Twitter's top legal and policy executive and the company's general counsel, the New York Times reported.
A few hours later, Musk tweeted, "the bird has been freed," a reference to Twitter's logo.
He had also tweeted a video of himself walking into the company's headquarters on Wednesday carrying a porcelain sink, posting: "Entering Twitter HQ — let that sink in!''
The Tesla CEO also changed his Twitter profile to refer to himself as "Chief Twit" and switched his location to Twitter's San Francisco headquarters.
What's next for Twitter and Musk?
On Thursday he shared a message in which he claimed the speculation over his intentions regarding the purchase of the platform had been "wrong" and that he was buying Twitter to "help humanity."
Twitter's stock had edged closer to Elon Musk's $54.20 (€53.72) per share buyout offer for the platform on Wednesday. That was a sign that investors expected the $44 billion deal to proceed ahead of a court deadline at the end of the week.
The Friday deadline to complete the deal was ordered by the Delaware Chancery Court in early October. The ruling followed an epic battle during which Musk signed a deal to acquire Twitter, then tried to withdraw from it. Twitter subsequently sued the Tesla CEO to force him to go through with the deal.
If the parties don't meet the deadline, another legal hearing could take place in November.
Many Twitter users have expressed concern over Musk's pledge to protect "freedom of speech" on the platform including mulling the option of reinstating former President Donald Trump who was kicked off Twitter for his connections with the January 6 riots at the Capitol in Washington.
The deal to put the social media platform into the hands of the richest person in the world has also raised concerns.