Musk has a history of being unconventional, posting irreverent tweets, and it was not immediately clear whether he planned to pursue a Manchester United deal.
Below are some other tweets by Musk - who has more than 103 million followers - which have taken investors, Twitter users, Twitter's board and the rest of his audience than by surprise.
May 13, 2022: "Twitter deal temporarily on hold pending details supporting calculation that spam/fake accounts do indeed represent less than 5% of users." Twitter had agreed with Musk on his $43 billion takeover of the social media company, after initial hiccups, and its shares fell sharply after Musk's tweet.
The billionaire later terminated the deal saying that Twitter withheld information about these accounts, and the two sides are currently readying for a trial scheduled to begin Oct. 17 in Delaware.
April 27, 2022: "Next I'm buying Coca-Cola to put the cocaine back in." Musk's tweet, an apparent joke, came days after he made his buyout offer for Twitter.
Aug. 7, 2018: "Am considering taking Tesla private at $420. Funding secured." Musk was not close to taking Tesla private and had not lined up financing, and the number 420 is closely associated with marijuana use. Tesla shares jumped, and the U.S. Securities and Exchange Commission went on to sue Musk, saying he had misled investors.
April 1, 2018: "Despite intense efforts to raise money, including a last-ditch mass sale of Easter Eggs, we are sad to report that Tesla has gone completely and totally bankrupt," Musk said in an April Fool's day tweet. Tesla shares fell 5.1% the following day.
Jan. 27, 2018: "When the zombie apocalypse happens, you'll be glad you bought a flamethrower. Works against hordes of the undead or your money back!" Musk's Boring Co sold flamethrowers and hats to raise funds for its Hyperloop transportation project.
July 25, 2017: "I've talked to Mark about this. His understanding of the subject is limited." Musk was targeting Mark Zuckerberg, chief executive of Facebook owner Meta Platforms Inc, who downplayed Musk's warnings about the danger of artificial intelligence.
March 12, 2015: "The rumor that I'm building a spaceship to get back to my home planet Mars is totally untrue." Musk has said he wanted his company SpaceX to develop a rocket capable of an unpiloted trip to Mars in 2022, with a crewed flight two years later.
(Reporting by Shubham Kalia in Bengaluru; Editing by Kenneth Maxwell)