Musk provided few details, but the tweet from his official account will ignite havoc in the tech and financial worlds. Twitter shares extended their fall in pre-market trading.

“Twitter deal temporarily on hold pending details supporting calculation that spam/fake accounts do indeed represent less than 5% of users,” Musk said.

The company’s shares plunged more than 17% in pre-market trading in response to the news. Tesla’s shares rose about 5%.

The big picture: Musk’s takeover bid has been wrought with so many twists and turns that Wall Street is beginning to feel skeptical that it will even happen.