Philippine authorities rescued 14 protected sea turtles that were caught in a net laid down by Chinese poachers, a navy commander said Saturday.

However one sea turtle was already dead when a joint team from the navy and the environment department arrived Friday in the remote area off the western island of Palawan, said Major Ferdinand Atos.

Atos, commander of naval forces in the area, said informants had told them that Chinese poachers planted the net a week ago in the coastal district of Balabac.

"They enter the waters of Balabac, riding in a speedboat and they plant their nets, using their contacts among the locals," he told AFP.

The 200-metre (660-foot) net left by the poachers was removed and the 14 surviving sea turtles were set free, Atos said.

He said informants had told them that Chinese fishermen used their contacts to enter the area frequently and would bring their catch to Half-Moon Shoal, an outcrop in the Spratly islands claimed by both the Philippines and China.

The shoal has come under closer scrutiny after China announced that one of its naval frigates had run aground there.

Sea turtles are protected under Philippine law and catching them is punishable by at least 12 years in jail.

Chinese fishermen poaching in Philippine waters have become an issue in recent months.

In April, Philippine authorities tried to arrest Chinese fishermen taking sea turtles and other protected species from Scarborough Shoal in the South China Sea.

They were blocked by Chinese government ships, triggering a continuing standoff over the area which is claimed by both countries.