NICOSIA (Reuters) - Police in Cyprus said they believed they foiled an assassination attempt against the island's chief prosecutor, the attorney-general, after the arrest of three men in the capital Nicosia.

Acting on a tip-off, authorities on the east Mediterranean island discovered an anti-tank missile, explosives and detonators in a basement on Sunday evening.

"It appears the target was the attorney-general," a police spokeswoman said, declining to give further details.

The three men, all Cypriots, were being held on suspicion of conspiracy to commit murder, and illegal possession of explosives.

Attorney-general Petros Clerides, appointed in 2005, is the state's top legal adviser and prosecutor. He is also responsible for recommending pardons for convicted criminals.

(Writing by Michele Kambas; Editing by John Stonestreet)