Donald Trump's national security adviser, Michael Flynn, partnered this year with a controversial technology company co-run by a man once convicted of trying to sell stolen biotech material to the Russian KGB espionage agency.

Subu Kota, who pleaded guilty in 1996 to selling the material to an FBI agent posing as a Russian spy, is one of two board directors at the company, Boston-based Brainwave Science. During years of federal court proceedings, prosecutors presented evidence they said showed that between 1985 and 1990 Kota met repeatedly with a KGB agent and was part of a spy ring that made hundreds of thousands of dollars selling U.S. missile defense technology to Russian spies. Kota denied being part of a spy ring, reached a plea agreement in the biotech case and admitted to selling a sketch of a military helicopter to his co-defendant, who was later convicted of being a KGB operative.