Malaysia navy ships scrambled on Sunday to rescue 31 people including 28 Chinese tourists aboard a boat which sank off the coast of Borneo, maritime officials and Chinese state media reported.
Passengers were in the water awaiting help, China's consulate general's office in Kota Kinabalu said, according to China's official Xinhua news agency. Malaysian officials were unable to immediately confirm the report.
The boat left Kota Kinabalu, the capital of Malaysia's eastern Sabah state, at about 9 a.m. (0100 GMT) on Saturday bound for the popular tourist spot of Mengalum island, Malaysian officials said.
It was reported missing at about 9.50 p.m. after failing to arrive at the island and a search operation was launched soon after, Sabah and Labuan Malaysian Maritime Enforcement Agency (MMEA) deputy director Rahim Ramli said.
Bad weather was hampering the search effort, which covers an area of about 400 nautical square miles.
"We are looking at strong winds and choppy waters," he said.
The Malaysian navy, maritime police and air force were involved in the search, the MMEA said in a statement.
The Chinese consulate in Kota Kinabalu earlier on Sunday asked the state government to step up the search effort, Xinhua reported.
The China National Tourism Administration said it has initiated emergency response procedures.