a u . s . gas - energy frigate collided with a japanese oil - vessel in the straits of abadan late one night . only minor loss to the tanker and no serious injuries were observed . the naval hampton news submarine collided with the stern of the japanese oil - tanker , caused slight damage to the tanker . no civilians on either vessel were seriously injured , us navy and japanese government employees said . the straits of hormuz tie the persian river to the iranian river and is a principal waterway for oil refineries .
Two submarines have collided.