Updated

Iran's nuclear chief says authorities have arrested four workers on charges of planning sabotage in one of the country's nuclear facilities.

Sunday's report by the semiofficial Fars news agency gives no further details on the alleged plot, but says authorities had monitored the suspects and made the arrests at "exactly the right time."

Nuclear chief Ali Akbar Salehi was quoted as saying the suspects were being interrogated.

Iran periodically announces the arrest of suspects charged with espionage or attempts to sabotage its nuclear facilities. But it normally does not release further details on their identities or fate.

Iran accuses Israel and its allies of plots to undermine Tehran's nuclear program, which West suspects could eventually produce nuclear weapons. Iran denies the claims.