MANILA, Philippines — Satellite imagery released by a Washington-based think tank confirm reports that Chinese vessels, including fishing, coast guard and navy ships had been operating near Pag-asa Island in the West Philippine Sea.

Earlier this week, Magdalo Partylist Rep. Gary Alejano released a timeline of recent Chinese incursions in the West Philippine Sea.

Alejano cited military sources, claiming that at least two fishing ships, two Chinese naval vessels and a Chinese Coast Guard ship were operating around Pag-asa Island by August 12.

“The Chinese may have a sinister plan to occupy sandbars just west of Pag-asa that belong to us," Alejano said.

Neither Defense Secretary Delfin Lorenzana nor Foreign Secretary Alan Peter Cayetano has confirmed or denied the claims of Alejano.

Cayetano only said that the Philippines should not be alarmed by the reported presence of Chinese vessels in the second biggest island in the Spratlys.

On Thursday, the Asia Maritime Transparency Initiative (AMTI) released photos showing nine Chinese fishing ships and two naval/law enforcement vessels visible near the island by August 13.

"It is impossible to know if any of those ships might be affiliated with the maritime militia, but at least two appear to be actively fishing (locations 6 and 8), with their nets visibly in the water," the AMTI said.

A Philippine fishing boat was also spotted near one of the unoccupied sandbars near Pag-asa Island, possibly sent to investigate Chinese presence.

According to the think tank, the fishing vessels were all located between one and five nautical miles from the island while the nearest law enforcement ship is about 3.6 nautical miles from Pag-asa.

The ships are also near Chinese-occupied Subi Reef positioned between 9 and 14.25 nautical miles to the southwest of the disputed feature.

"It is important to note that ownership of the territorial waters in which these ships are operating is still legally disputed. Subi was a low-tide elevation before China built an artificial island on it," AMTI said.

The Chinese ships may all be operating within the territorial sea of both Pag-asa Island and the sand cay with which Subi Reef is located.

One possibility of the presence of Chinese flotilla in the area is that Beijing wanted to discourage Manila from its planned construction on Pag-asa.

Earlier this year, Lorenzana visited the island amid government plans to conduct upgrades including a beaching ramp, desalination facilities and repairs to the island's runway.

"Those upgrades have been delayed, reportedly due to inclement weather, but Lorenzana has made clear that they remain in the pipeline. In light of this week’s events, Manila might feel that those upgrades are even more urgent," the think tank said.

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