A crew member died and 4 others went missing after fire broke out on a new Maersk Line container vessel in the Arabian Sea, the company said.
The vessel caught fire at around 11:20 p.m. on Tuesday (Manila time), about 900 nautical miles southeast of Salalah, Oman, the world's biggest container shipping company said in a statement.
Twenty-three crew members were rescued but 1 of them, a Thai national, died on Wednesday, added Maersk.
"His health condition drastically deteriorated ... due to the injuries sustained in connection to the fire," said Maersk, a unit of Danish shipping firm AP Moller-Maersk A/S .
The fire was still burning on Wednesday and searches were still going on for 4 other crew members who went missing after the blaze, it added.
"This is a very serious fire," a company spokeswoman said. "At this stage we have no reason to believe the fire was caused by an error in the ship's construction."
The Maersk ship was en route from Singapore towards Suez. Two of the evacuated crew members received medical aid onboard another container vessel en route to Colombo, Sri Lanka, Maersk said.
The 27-strong crew included 13 from India, 9 from the Philippines, 2 Thai nationals and 1 each from Romania, South Africa and the United Kingdom.
Maersk did not disclose the identity of the 4 missing crew members, but said relatives had been informed.
Maersk said the crew of Maersk Honam sent out a distress signal after unsuccessful firefighting efforts on Tuesday.