A sand dredger capsized on Wednesday off Malaysia in the Malacca Strait, killing one Chinese sailor and leaving 14 others missing, authorities said on Thursday.

Three Chinese out of the 18 crew members on board were rescued and one was found dead. The other 14 people－12 Chinese, one Indonesian and one Malaysian－remain missing, the Ministry of Transport said.

A Chinese rescue team of seven－five divers, an engineer and a business representative－was dispatched by the China Maritime Search and Rescue Center and arrived in Malaysia on Thursday morning.

Malaysia's coast guard sent seven rescue boats to the scene after they were alerted at around 8:30 am on Wednesday that the vessel had overturned, the ministry said in a statement.

Sanifah Bin Yusof, deputy director of the southern region of the Malaysian Maritime Enforcement Agency, the country's coast guard, told Xinhua News Agency that at least some of the missing appeared to be stranded inside the ship.

"We checked the ship and had good communication when we knocked on the hull of the ship, got some responses from the inside," he told Xinhua at the operation center. "We are trying to save their lives with a diving operation."

Ahmad Kamarulzaman Ahmad Badaruddin, chief of the Malaysian Navy, said a Navy vessel has been dispatched with a diving team to join the operations.

The dredger capsized 8.5 nautical miles off Parit Jawa in the southern Malaysian state of Johor, with the cause and exact time of the incident still unknown, according to the ministry.

The Ministry of Transport said it is paying great attention to the accident, and will strengthen cooperation with Malaysia and spare no effort to rescue the missing sailors and treat the wounded.