ROME (Reuters) - Italy seized more than 24 million tablets of a synthetic opiate that Islamic State militants planned to sell to finance attacks around the world, the head of a southern Italian court said on Friday. The pills were seized by finance police and customs officials in the container port of Gioia Tauro, Italy s biggest, according to a statement. The U.S. Drug Enforcement Administration collaborated in the investigation.  A video shows police opening a container filled with boxes of Tramadol, a powerful painkiller normally available only on prescription.  With an average sale price of about 2 euros ($2.33) per tablet, the haul was worth 50 million euros, the statement said. Foreign investigators told the court in the city of Reggio Calabria that the drugs belonged to Islamic State. The drugs sales were  managed directly by Islamic State to finance the terrorist activities planned and carried out around the world , Reggio Calabria s chief prosecutor Federico Cafiero De Raho said.   Part of the illegal profit from their sale would have been used to finance extremist groups in Libya, Syria and Iraq,  he said. The seizure comes three days after an Uzbek immigrant, Sayfullo Saipov, drove a truck on a New York City bike path, killing eight, in the latest attack claimed by Islamic State. No details on how the illegal shipment was discovered or on its final destination were provided by the court. A similar shipment was discovered in Greece last year, and an even larger one was found in Italy s Genoa port in May. 