Seven Greek seamen were crewing a Greek-captained World War II torpedo boat apprehended off the coast of Spain on Thursday with 3.6 tons of cocaine on board, the Merchant Marine Ministry said yesterday. The eighth crewman on the Honduran-flagged Cork was a Dominican, while the ministry identified the captain as Greek national Fotis Patronis, 53. All eight were arrested by Spanish and British authorities who boarded the German-built Cork at 5 p.m. Greenwich Mean Time (8 p.m. Greek time) some 420 miles off Vigo on Spain’s Atlantic coast. A British frigate and military helicopters took part in the operation. One of the largest hauls ever in the area with an estimated street value of $400 million, the drugs are believed to have come from Colombia and were destined for the western European market. Merchant Marine Ministry sources quoted by the Athens News Agency said the decommissioned, 42-meter torpedo boat was believed to be Greek-owned. On April 14, Spanish authorities in the Atlantic found 2.5 tons of cocaine on the Greek-owned trawler Irene.