Three Chinese Coast Guard ships were spotted 35 nautical miles or around 65 kilometers off the coast of El Nido, Palawan on Sunday morning, a maritime security expert said.

"Three China Coast Guard ships moved south from Scarborough Shoal to conduct an intrusive patrol within 35 nautical miles of northern Palawan, Philippines today", retired US Air Force Col. Ray Powell said in a post in X (formerly Twitter).

Powell said that the intrusive patrols of China are "meant to establish a continuous presence and gradually normalize Chinese jurisdiction over areas granted to its neighbors under international law".

"I think they're getting pretty close. I'm not sure it's alarming but it's certainly concerning ... It's becoming more common so we're starting to see more of these intrusive patrols near Palawan" Powell said in a television interview.

The monitored Chinese Coast Guard ship immediately left, according to a television report. Marie Manalili/DMS