Metro Manila (CNN Philippines, December 15) — A number of Chinese vessels were spotted in parts of the West Philippine Sea in recent weeks, according to the military.

A photo released Thursday by the Armed Forces of the Philippines Western Command (AFP WESCOM) showed 12 Chinese fishing vessels stationed around the eastern portion of Sabina Shoal, which is within the country’s exclusive economic zone.

The shot was taken in late November, according to WESCOM. Chinese ships were also observed in the same area on Dec. 5, it added.

The Department of National Defense earlier raised concerns over the reported swarming of Beijing’s vessels in WPS waters, stressing that any violation of the Philippines’ sovereign rights is unacceptable.

The Department of Foreign Affairs, on the other hand, said it was still awaiting official details.

Admin urged to take tougher stance vs. China

Some House lawmakers meanwhile called on the Marcos administration to take a tougher stance against China amid its incursions in the contested waters.

ACT Teachers party-list Rep. France Castro said the government should go beyond filing diplomatic protests.

“Hinahamon natin ang administrasyong Marcos sa pagharap. Hindi na uubra ngayon ‘yung mga pasulat-sulat o pagbibigay ng mga protest na letter sa China,” Castro said in a press briefing together with members of the Makabayan bloc.

[Translation: We challenge the Marcos administration to face the issue. Sending protest letters to China just won’t do anymore.]

CNN Philippines’ Xianne Arcangel contributed to this report.