Manila, April 30 -- Three Chinese research vessels were detected within the vicinity of the Ayungin Shoal, a ranking Philippine Navy (PN) official said Tuesday.

In a press briefing, PN spokesperson for the West Philippine Sea Commodore Roy Vincent Trinidad said these vessels were detected on Monday, adding this is the first time such vessels were monitored in the area.

"I could remember we have not recorded or reported any research vessel so far from China in Ayungin Shoal," Trinidad said.

Asked on the Chinese research vessels' possible purpose, the PN official said it is likely China's way of showing that it is not bothered by the ongoing "Balikatan" exercise between the Philippines and the United States.

"It coincided with 'Balikata...