Iranian officials said Monday that 17 people have been captured who were allegedly spies working for the U.S. Central Intelligence Agency.

The Iranian Intelligence Ministry held a briefing on Monday where they announced the alleged spies were Iranian citizens but trained by the CIA.

Some of those arrested have been sentenced to death, the Intelligence Ministry said.

It was not immediately clear when they were arrested.

U.S. officials have not yet responded to the allegations. The Iranian government occasionally makes similar claims and it was not immediately possible to determine whether they are legitimate. The U.S. government never acknowledges CIA recruitment abroad.

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