CIA turncoat Aldrich Ames, who died at 84 in a US prison, sold secrets to the erstwhile Soviet Union until his arrest in 1994. Ames, whose codename was ‘Kolokol’ (The Bell), revealed the identities of over 30 agents spying for the West, leading to the execution of at least 10 CIA assets. He reportedly compromised more than 100 clandestine operations.