Ten foreign tourists are missing after a boat travelling between islands in eastern Indonesia sank, while 10 others had been rescued, search and rescue officials say.

Five Indonesians, the boat crew and a tour guide were also missing after the vessel hit a reef and went down on Saturday. It had been heading from Lombok island to Komodo island, the home of the Komodo dragon, the world’s biggest lizard and a draw for tourists.

Those rescued were from New Zealand, Britain, Spain, the Netherlands, Germany and France, said Budiawan, a search and rescue official who goes by one name. The nationalities of those still missing was not immediately clear.

“A tourist boat with 25 people on board capsized while sailing from Lombok island to Komodo island,” said Budiawan, who is based on Lombok.

“We rescued 10 foreigners while 10 other foreigners and five Indonesians remain missing. We launched a search operation as soon as we received the report (Sunday) morning.”

The boat went down near Bima, a town on Sumbawa island. Suryaman, a search and rescue official in the town, said the boat sank in the early hours of Saturday but those rescued were not recovered until the evening of the same day.

“The incident took place … when the boat hit a reef and sank. Fishermen managed to rescue five of them alive later at night on Saturday, and five other foreigners were rescued by a sailing boat,” Budiawan told AFP.

An official from the national search and rescue agency said the five Indonesians included four boat crew members and a tour guide.

A spokesman for the British embassy in Jakarta said: “We are aware of an incident close to Bima earlier today and that British nationals might be involved.

“We are in touch with the local authorities and stand ready to provide consular assistance.”

Komodo island is one of several islands that make up the Komodo National Park, a protected area that is home to the Komodo dragon. The huge lizards can grow up to three metres long and have a venomous bite.

Indonesia relies heavily on boats to connect its more than 17,000 islands, but has a poor maritime safety record.

Two vessels sank last month in different parts of the archipelago as millions travelled for the Muslim Eid holiday, leaving at least 36 people dead.