Fifty years of spies

Aldrich Ames betrayed at least a dozen CIA agents

A brief look through high-profile spy cases in the USA since World War II shows ideological reasons giving way to financial.

Klaus Fuchs

Physicist Klaus Fuchs was arrested and convicted in 1950 of giving US and British atom bomb research to the USSR.

A German Communist, Fuchs fled to Britain when Hitler came to power in 1933.

He worked on the atom bomb at the top-secret laboratory at Los Alamos, New Mexico, from 1943-45.

Fuchs was sentenced to 14 years in prison but released in 1959 for good behaviour. He then emigrated to East Germany.

Julius and Ethel Rosenberg

Jonathan Pollard: life sentence for spying for Israel

Communists Julius and Ethel Rosenberg were given the death sentence in 1953 for passing nuclear weapons data to a Soviet agent.

They acquired the information from Ethel's brother, Sergeant David Greenglass, who worked on the Los Alamos project.

Greenglass was given a 15-year prison sentence after testifying against the Rosenbergs.

Christopher Boyce

Christopher Boyce was arrested in 1979 for selling US spy satellite secrets to the Soviet Union.

He worked for military contractor TRW in California, using his friend Andrew Lee as courier.

The story of their case was told in the best-selling book The Falcon and the Snowman.

In 1980 Boyce escaped from a federal prison and carried out several bank robberies before being arrested in Washington state.

John A Walker Jr

Retired Navy warrant officer John A Walker Jr was sentenced to life imprisonment in 1985 after spying for the USSR for over 20 years.

He set up a spy ring after losing money on investments. The ring included his son, his brother and navy radio officer Jerry Whitworth.

It gave Soviet agents cryptographic secrets and more than one million messages on US weapons, naval tactics, and submarine and airborne training.

Jonathan Pollard

Jonathan Pollard, a naval civilian intelligence analyst, was convicted in 1986 of spying for Israel.

Pollard gave the Israelis information on code-breaking and on US agents and contacts.

Israel paid Pollard as much as $2,500 a month for spying, as well as $30,000 cash bonuses.

Pollard pleaded guilty to espionage and was given a life sentence.

Aldrich Ames

Former Central Intelligence Agency officer Aldrich Ames was sentenced to life imprisonment in 1994 for spying for the former Soviet Union and Russia from 1985 to 1991.

Ames told investigators that he had betrayed at least a dozen Russian and Eastern European agents recruited by the CIA, for which he received $2m.