NEW YORK (Reuters) - The U.S. Justice Department's top prosecutor in San Francisco is targeting artificial intelligence (AI) and other tech start-ups that defraud investors before they go public, he told Reuters.

Ismail Ramsey, who became U.S. attorney for the Northern District of California a year ago, said his office is uniquely positioned to crack down on tech start-ups that mislead investors on the path to initial public offerings (IPOs) given his proximity to Silicon Valley venture and angel investors.