WASHINGTON (Reuters) - A federal grand jury has indicted prominent activist short seller Andrew Left on multiple counts of securities fraud for a long-running $16 million market manipulation scheme, the U.S. Justice Department said on Friday.

The indictment, filed on Thursday, said Left "commented on publicly traded companies, asserting that the market incorrectly valued a company's stock and advocating that the current price was too high or too low," the Justice Department said in a statement.

Left, 54, of Boca Raton, Florida, made recommendations as a commentator on multiple cable business news channels, on his X social media account and a website, it said.

"The commentary routinely included sensationalized headlines and exaggerated language to maximize the reaction it would get from the stock market," the department said.