After rumors and suggestions of Tesla's September sales slowing caused the automakers' shares to drop 5 percent Monday, CEO Elon Musk took to social media to shoot down the report. After the tweet, Tesla shares gained more than 2.5 percent in premarket trading Tuesday.

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The Wall Street Journal reported that WardsAuto.com said Tesla's (TSLA) U.S. sales were down 26 percent over the last nine months.

In response to the report, Musk fired back on Twitter (TWTR) on Tuesday, calling the sales figures quoted in the article "incorrect."

Keep in mind, Tesla has never reported monthly sales; it announces results on a quarterly basis. The next time Tesla is expected to report sales is early November.

The news comes a day after Tesla introduced a new leasing policy for the automaker's new Model S, with an option for buyers in the U.S. to return the car within three months of purchase. Musk insisted the new leasing program doesn't constitute a discount.

Read More Tesla offers leasing options for new Model S in US

In a report on Dow Jones News Service, the company didn't comment on Musk's tweets. Dow Jones News Service and the Journal are owned by News Corp. (NWSA)

-CNBC's Phil LeBeau and Reuters contributed to this report.