A speedboat carrying 11 European tourists has gone missing off the coast of Indonesia. Rescuers are searching for a speedboat that went missing off a bay on Sulawesi island, officials said on Saturday.

The vessel departed from the Central Sulawesi province on Friday morning bound for Marisa Port in the neighboring Gorontalo province, but failed to arrive as scheduled, the head of the Gorontalo Province Search and Rescue Office said.

The missing boat was reported by a local tour guide and search and rescue operation started at around 3.40pm on Friday (local time). “Concerns arose when their speedboat had not arrived by afternoon,” the search and rescue office said. “We immediately launched a search mission overnight but until now have not found any signs” of the vessel or people on board, officials added.

Authorities also said a Czech man, a Belgian man, five Dutch nationals, three Germans, a French woman, and two Indonesian crew members were on board. There was no immediate comment from the embassies representing the missing tourists.

Search operations are covering approximately 300 square nautical miles of waters along and around Tomini Bay, which is a renowned marine tourism destination. A thermal-imaging drone and diving equipment are also being used.

Indonesia is an archipelago with more than 17,000 islands, where boats are a common form of transportation. With lax safety standards and problems with overcrowding, accidents occur frequently.

On July 15, a passenger boat carrying 76 people sank off Selayar Island, killing at least four people and leaving 14 others missing.