TEHRAN, Iran (AP) - A team of six Indian divers conducting underwater pipeline installation were believed trapped in a diving chamber nearly 200 feet underwater with dwindling oxygen supplies on Friday after their support ship sank in the Persian Gulf, Iranian officials said.
    
The divers were among 13 people, including five Iranians and eight non-Iranians, still missing after the Koosha-1, a diving support ship, went down in stormy seas Thursday afternoon, Iran's semi-official Isna news agency reported. Out of 73 people on board, 60 had been rescued, Isna said.
    
The diving chamber was onboard the ship when it sank, but the divers were inside because they stay in the sealed environment to avoid having pressurize and depressurize for their dives.
    
"We hope their oxygen has not run out," said Pirouz Mousavi head, of the Pars Energy Zone in southern Iran, quoted by Isna. "We have deployed divers to save those who are trapped in the chamber," which he said was about 180 feet (60 meters) underwater.
    
The chamber can hold 72-hours worth of oxygen, said Z. Hussain, a manager at Adsun Offshore Diving Contractors Pvt Ltd, the Mumbai, India-based firm that employs the divers. But he said he did not know how much supply there was when it went down.
    
"The ship sunk in a matter of minutes and the six men in the chamber were trapped underwater," he said. "They've been underwater, it is almost 24 hours," he said.
    
Other rescue teams were searching for the other missing. Mousavi spoke of 13 still missing, with no confirmed deaths, but a local, official, Ahmad Moradi, said the bodies of six had been found, including an Indian and an Ukrainian.
    
Calls to Dubai-based Dulam International that is leading the rescue operation were not immediately returned.
    
The Iran-flagged Koosha-1 had left Thursday from offshore oil rigs near the underwater South Pars gas field, the largest in the world that is shared by both Iran and Qatar. The ship had been involved in installing underwater pipelines. It sank in the Persian Gulf some 15 miles (25 kilometers) off Iran's coast.

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