Manila- A cargo vessel sank off a central Philippine province Thursday, but all 13 people aboard were able to swim to safety, the coast guard said.

The vessel was 50 metres away from a private wharf in Cebu province, 585 kilometres south of Manila, when it "suddenly submerged" and its officers and crew were able to swim to the wharf, a coast guard report said.

Teams set up markers in the waters to monitor for a possible oil spill from the sunken vessel, which was carrying gravel, the coast guard said.

A large portion of the Philippines has been experiencing bad weather because of the south-west monsoon, which was enhanced by Typhoon Sinlaku.

Sinlaku intensified slightly as it slowly moved away from the Philippines toward Taiwan, the weather bureau said.

It warned that Sinlaku would continue to enhance the south-west monsoon and bring rains over the northern region of Luzon and the central region of Visayas.

Sinlaku was packing maximum sustained winds of 175 kilometres per hour and gusts of up to 210 kilometers per hour, the weather bureau said. (dpa)