The death toll after a boat carrying hundreds caught fire in eastern Indonesia has risen to 17, officials said Tuesday.

The KM Express Cantika 77 erupted into flames off the coast of Timor island in East Nusa Tenggara province on Monday, prompting desperate passengers to jump overboard.

The boat's top deck set alight as it sailed from provincial capital Kupang to the town of Kalabahi on Alor island.

The head of a local search and rescue agency, I Putu Sudayana, said the death toll had increased from 14 after three bodies were found at sea a day after the incident.

Rescuers found 312 survivors and recovered 17 bodies after the fire at sea, Sudayana said.

He said the search operation would continue for a week as the number of passengers was unconfirmed.

"It's not clear, because the (passenger) manifest is not certain," he told AFP.

Isyak Nuka, the head of East Nusa Tenggara transportation agency, gave the same death toll but a lower number of 311 survivors after the fire.

"We don't exactly know how many people were on board, because the number of survivors is already higher than the (passenger) manifest of 167 people," he told AFP.

Marine accidents are common in the Southeast Asian archipelago of around 17,000 islands, where safety standards are often lax.

In 2018, more than 150 people drowned when a ferry sank in one of the world's deepest lakes on Sumatra island.

AFP