China planning to send robot sub to sunken ship

China's Transport Ministry says preparations are underway to send a robot submarine possibly followed by divers to explore and plug holes in a sunken Iranian oil tanker whose 32 crew members are all believed to have died.

The Shanghai Maritime Search and Rescue Centre and a Hong Kong newspaper on Wednesday say authorities will send larger salvage vessels to support the operation.

China says the Sanchi is lying under 115 meters (377 feet) of water in the East China Sea. It caught fire after colliding with a freighter on Jan. 6 and exploded and sunk on Sunday about 530 kilometers (330 miles) southeast of Shanghai.

The report says an expanding slick from its cargo of natural gas condensate is being monitored for potential environmental damage with cleanup efforts being organized.