File photo.

Police arrested a man in Athens on Saturday after finding a hand grenade in his possession during an operation by the Organized Crime Division, authorities said.

The suspect had reportedly been under surveillance for some time after authorities received indications that he was preparing to carry out an attack, state broadcaster ERT reported.

According to the same reports, the man had allegedly been ordered to target the home of a judicial official. Authorities have not disclosed the identity of the intended target or the location of the residence.

Police intervened before any attack could take place, arresting the man at the home of an associate in Athens’ southern suburbs, where he had allegedly obtained the grenade.