Damian Williams, the top federal prosecutor in Manhattan, was expected to address the charges in a press conference. Williams, nominated to the role by President Joe Biden, has made enforcement of financial crimes a focus since taking office last year.

The U.S. Securities and Exchange Commission filed related charges over various trading schemes.

Among those charged were Brijesh Goel, a former employee of an unnamed investment bank who provided a co-conspirator with internal, non-public information about potential mergers and acquisitions beginning in February 2017, according to an indictment unsealed on Monday.

The co-conspirator, identified by the SEC as Goel's friend Akshay Niranjan, used the tips to trade in securities of some of those companies and then split approximately $280,000 in profits with Goel, prosecutors said.

Goel faces five securities fraud counts and one count of obstruction of justice.

Prosecutors also charged Seth Markin, the former FBI trainee, with insider trading for allegedly buying shares of Pandion Therapeutics Inc before a February 2021 tender offer for the company by Merck & Co.

Markin allegedly learned of the deal by secretly reviewing documents belonging to his then-romantic partner, who worked at a law firm representing Merck.

In a third case, prosecutors said Amit Bhardwaj, a former executive at laser and optical fiber specialist Lumentum Holdings Inc, last fall bought shares in Coherent Inc after learning that Lumentum planned to acquire the company.

Lawyers for Goel, Markin and Bhardwaj could not immediately be identified.

Prosecutors separately announced charges against Stephen Buyer, a former U.S. congress member, for buying shares in Sprint after learning of rival T-Mobile's plans to acquire the firm in 2018.

Buyer was working as a consultant to T-Mobile at the time, prosecutors said.

(Reporting by Luc Cohen in New York; Editing by David Gregorio)