A tanker owners' group has urged governments to do more to combat piracy in the Indian Ocean, saying hijackings could disrupt global oil supplies. It said Somali pirates were now using at least 20 seized vessels as mother ships to launch attacks in the region. The warning follows the latest hijacking by of a supertanker carrying some 200 million dollar worth of crude oil off the coast of Oman. The head of the International Association of Independent Tanker Owners Joe Angelo said the piracy situation is now spinning out of control into the entire Indian Ocean. He said if piracy in the Indian Ocean is left unabated, it will strangle these crucial shipping lanes with the potential to severely disrupt oil flows to the US and to the rest of the world.