A Manhattan grand jury indicted eight defendants in a nearly $300 million pump-and-dump stock fraud scheme, The Post has learned.

Some of the defendants are stock promoters who allegedly became criminally involved with employees in penny stock companies to manipulate the market and defraud thousands of investors, sources said.

The accused financial fraudsters proved misleading and false information about a stock to attract buyers, boosting its share price.

Then the ringleaders would sell their sizable holdings at the artificially inflated price, causing the value of the stock to plummet and fleece investors who paid top dollar for it.

The traders face grand larceny, scheme to defraud and criminal possession of stolen property raps, said the indictment, expected to be unsealed Thursday.

Several of the defendants, a majority of whom are based in California and Florida, including Joseph Dervali, are expected to turn themselves into the Manhattan District Attorney’s Office Thursday and be arraigned before Justice Roger Hayes in the afternoon.