Twitter shares closed 18 percent lower after the social media company's disappointing quarterly report leaked early.
Twitter's first-quarter profit beat Wall Street's expectations but sales fell short of estimates. The social media company posted adjusted first-quarter earnings of 7 cents per share on revenue of $436 million.
Financial intelligence service Selerity posted four tweets after 3 p.m. ET Tuesday with what it said were first-quarter earnings, revenue and user figures. Twitter issued a press release about 25 minutes later confirming Selerity's figures.
The New York Stock Exchange said Tuesday afternoon that it is reviewing trades made at 3:47 p.m. ET.
The 18 percent slide marked Twitter's second-worst day ever, trailing only a 24 percent drop in February 2014. Twitter shares were choppy in extended trading.
Wall Street had expected Twitter to post earnings of 4 cents per share on $457 million in revenue.
Revenue jumped 74 percent from the year-earlier period, but the total was worse than even the most pessimistic of the 36 analyst estimates compiled by Thomson Reuters.
The company's second-quarter revenue outlook of $470 million to $485 million was also well below the average Wall Street forecast of $538 million.
"We anticipate the factors that affected our first-quarter results will also affect our 2015 guidance," Twitter CEO Dick Costolo said in the company's earnings call.
Costolo is slated to appear on CNBC's "Squawk Alley" at 11:30 a.m. EDT on Wednesday.
"This is a company that is still experimenting with parts of monetization across many different fronts. I think these are still very, very early days," said Chris Sacca, managing director at Lowercase Capital and an early investor in Twitter.
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Average monthly active users (MAUs) came in at 302 million for the quarter, in line with expectations and up 18 percent year-over-year. Mobile MAUs—which accounted for about 80 percent of the total—fell short of Wall Street's estimates, though.
Twitter—which owned a 1.6 percent share of the digital advertising market last year, according to eMarketer—saw advertising revenue jump to $388 million, up 72 percent year-over-year. Mobile advertising accounted for 89 percent of the total.
Even with its ad business growing, Twitter's share of the digital market lagged well behind the 10.4 percent held by Facebook last year.
"Certainly there is some disappointment but I think this reaction might have been a little bit overdone based on how the news came out," said Kenny Polcari, director of O'Neil Securities, on CNBC's "Closing Bell."
Twitter said it was "investigating the source of the leak."
—CNBC's Karma Allen contributed to this report