A catamaran boat carrying 31 people, including 28 Chinese tourists, went missing off the Borneo coast on Saturday, Reuters reported. Malaysian authorities said the catamaran was headed towards the Mengalum island from Kota Kinabalu, the capital of the country’s Sabah state.

Malaysian Maritime Enforcement Agency Deputy Director Rahim Ramli said the boat was reported missing at 9.50 pm on Saturday evening after it failed to arrive at the island, which is a popular tourist destination. Ramli added that bad weather was hampering search and rescue efforts. “We are looking at strong winds and choppy waters, and have requested assistance from the air force to conduct an aerial search,” he said.

Other than the tourists, a skipper and two crew members were also on board, reported AFP. The owner of the boat had reported it missing on Saturday evening.

Rescuers are searching an area of about 400 nautical square miles, he said. China has also activated a search for the boat itself and set up an emergency team led by the tourism administration, reported the state news agency Xinhua.