Chinese officials say they are still debating whether to raise an Iranian oil tanker that sank last month with the loss of all 32 crew members.
Chinese transport ministry officials told reporters Thursday that 1,900 tons of the Sanchi's fuel oil and some of the tanker's natural gas condensate cargo remains trapped underwater.
Officials say the remaining oil could explode or pose other dangers, complicating their plans to salvage the ship. Authorities are also trying to minimize the environmental damage.
The Sanchi caught fire after colliding with a freighter on Jan. 6 and exploded and sank days later about 530 kilometers (330 miles) southeast of Shanghai.
Three bodies were recovered from the sea and the tanker before it sank. Officials say no other bodies have been found.