Indonesia plans to prosecute the captain of a tourist boat for negligence after a fire ripped through the vessel on New Year's Day, killing at least 23 people and injuring dozens, police said on Tuesday.

The boat was carrying about 250 people before it was engulfed by flames shortly after leaving Jakarta.

Authorities were still searching the waters around the port for victims, while bodies retrieved from the charred ship were still being identified, said Hendra Sudirman, head of Jakarta's Search and Rescue agency.

After questioning, the captain had been named a suspect, police said.

"We have detained the captain of the boat since the incident. His status is now a suspect based on information from the crew, the passengers," Argo Yuwono, a spokesman for Jakarta's Metro Police, said on Tuesday.

Under the shipping law, if a captain causes deaths by sailing a ship knowing it is not seaworthy he can be jailed for up to 10 years. Negligence causing death under the criminal code is punishable by up to five years in jail.

Sea accidents are frequent in Indonesia, a sprawling archipelago, with vessels often overloaded, poorly maintained or having too few life jackets.