An alleged Chinese spy reportedly infiltrated Sen. Dianne Feinstein’s (D-CA) office by posing as her driver for 20 years, according to multiple reports.

Reports from Politico and the San Francisco Chronicle revealed the alleged Chinese government mole posed as a staffer in Feinstein’s San Francisco office— serving as the California Democrat’s driver, Asian-American community liaison, and stand-in for the senator at Chinese consulate events.

Politico reported that the staffer allegedly delivered non-top-secret political intelligence to Chinese consulate officials in San Francisco. Five years ago, the FBI told Feinstein—who served as chairwoman of the Senate Intelligence Committee—that her staffer was a spy.

The California Democrat was reportedly “mortified” by the news and fired the staffer but did not disclose the news to the rest of her staff.

The FBI could not charge the individual with espionage because none of what he leaked was considered to be classified information, making it difficult for the agency to prosecute him.

“Think about Diane Feinstein and what she had access to,” security analyst and former FBI agent Jeff Harp told KPIX. “One, she had access to the Chinese community here in San Francisco; great amount of political influence. Two, correct me if I’m wrong, Dianne Feinstein still has very close ties to the intelligence committees there in Washington, D.C.

Other Feinstein staffers also had links to foreign intelligence. A former Feinstein staffer who worked on the Democratic Senate Intelligence Committee hired former British spy Christopher Steele and Fusion GPS after Donald Trump was elected president to “expose Russian interference.”