MANILA - At least 20 people were reported missing after a fishing boat sank off in the southwest province of Palawan due to big waves, the Philippine Coast Guard said Tuesday.

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Coast Guard Spokesman Lt. Cmdr. Armand Balilo said its detachment in Linapakan, Palawan received on Sunday a call that FB Jonathan 1, which left Occidental Mindoro with 35 fishermen onboard, capsized approximately five nautical miles southeast of Canaron Island, Linapakan.

He said 15 fishermen were already rescued, while search and rescue operation is ongoing for 20 others, who are still missing.

"The boat captain reported that while on their way from Manamoc Island to Canaron Island, they encountered big waves and strong winds and the wooden freeboard at the forward portion of their fishing boat was detached from its frame and seawater subsequently flowed in. At that instance, subject fishing boat was reportedly half-submerged," Balilo said.

He said that the Coast Guard, Philippine Navy, Philippine Air Force and nearby fishing vessels have been conducting search and rescue operation in the area.