The last British-Soviet double agent from the Cold War George Blake Saturday died in Russia at 98 years of age.

Thee United Kingdom said he exposed hundreds of Western agents in Eastern Europe back in the 1950s, some of whom were executed due to his betrayel.

Alongside a group of British double agents known as the Cambridge Five, his treason was one of the most notorious during the Cold War.

After being exposed in 1961, he was sentenced to 42 years in prison. He escaped in 1966 and was smuggled out of  the UK with the help of fellow inmates and peace activists. Blake spent the rest of his life in the Soviet Union and Russia, and was treated as a hero.

In 1991, Blake told Reuters he had believed the world was on the eve of Communism, adding that “It was an ideal which, if it could have been achieved, would have been well worth it,” he said.