Aldrich Ames, a CIA officer who became one of America's most damaging double agents, has died aged 84. The former counterintelligence officer, who was serving a life sentence without the possibility of parole, died on Monday at the Federal Correctional Institution in Cumberland, Maryland, CBS News reported.

Ames was jailed on 28 April 1994 after he admitted to selling secret information to the Soviet Union and later Russia. He compromised more than 100 clandestine operations and divulged the identities of over 30 agents, resulting in the deaths of at least 10 CIA intelligence assets.

In need of cash, Ames began providing the KGB with named CIA spies in April 1985, receiving an initial payment of $50,000. Known by his KGB code name, Kolokol (The Bell), he later identified nearly all CIA spies in the Soviet Union, earning him substantial financial rewards.

Over nine years, Ames reportedly received around $2.5 million, which fueled a lavish lifestyle, including luxurious cars and expensive properties, despite his CIA salary being much lower. His espionage activities began when he cooperated with the Soviets, motivated primarily by debt rather than ideological beliefs.

Ames's espionage finally caught up with him in 1994 during a mole investigation, leading to his arrest. His actions were described by then-CIA Director R. James Woolsey as treachery that resulted in severe consequences for American agents.