Five Missing in Japan Refinery Tunnel Collapse

Divers were searching for five workers after an undersea tunnel collapsed at one of Japan's biggest oil refineries Tuesday, emergency services said.

Six people were in the partially constructed tunnel at Kurashiki, 550 kilometers (350 miles) west of Tokyo, when it caved in, but one managed to get out, a spokesman for the city fire department said.

The survivor "said that sea water came gushing in" and flooded the tunnel, according to the spokesman.

The accident happened at Mizushima Refinery, operated by JX Nippon Oil and Energy Corp.

"Police divers have begun their work searching for the missing," the spokesman said.

The refinery, which began operation in 1961, has capacity to process 365,000 barrels of oil per day and produces fuel oil, lubricant and various petrochemical products.

It also serves as a hub for the heavy industrial district of the city.

The tunnel, designed ultimately to be U-shaped, was about 11 meters (36 feet) in diameter and 30 meters deep, the fire department spokesman said. It stretched for about 140 meters.

Construction had begun in 2010, local reports said.

Aerial television footage broadcast by NHK showed muddy water littered with debris filling the vertical entrance shaft.

Several divers could be seen in the water, as many other emergency workers looked on.

JX Nippon Oil is Japan's largest oil company, which specializes in petroleum and petrochemical refinery, along with imports of gas and coal, according to the company website.