The Philippine government announced on Monday it will take legal action against China for harvesting giant clams at the disputed Scarborough Shoal in the South China Sea.

Filipino fishermen complained, with video evidence to back them up, that Chinese Coast Guard ships are blocking their access to the shoal and seizing their catches while Chinese fishermen harvest the clams. The Philippine government has tended to downplay these claims until now, stating they have no conclusive evidence of the Chinese physically harassing Filipino fishermen in the area.

That seems to have changed suddenly with the release of a report by ABS-CBN News in which Filipino fishermen talked about China’s bullying tactics and mass harvesting of claims in the area, a process that disturbs the water so much that other forms of fishing become impossible. Mud blasted up into the ocean by the clam harvesting process can actually endanger the health of spear and net fishermen, as well as making the water too cloudy to work in and driving away so many fish that the livelihood of Filipino fishermen is in serious jeopardy.

ABS-CBN reporters actually found at least 14 Chinese boats engaged in these activities and saw “pile upon pile of dead giant clams, each batch marked distinctly with yellow, green, and red labels.”

Only a few hours after colorfully refusing to engage in territorial disputes with China, Philippine Foreign Affairs Secretary Teodoro Locsin noticed a user sharing the ABS-CBN report on Twitter and said legal action is underway against the Chinese:

Earlier in the day, Locsin said it was not “the right time to bring up disagreements over the South China/West Philippine Sea with both sides hot under the collar while a pissing contest is in full flower,” by which he meant China’s relentless efforts to annex the entire South China Sea in defiance of international rulings.

Philippine President Rodrigo Duterte has generally taken a submissive posture towards Chinese aggression, arguing that his country benefits from trade with China and in any event cannot hope to win a military conflict against it.

Duterte’s tone has been changing as the Chinese push closer to the Philippine home islands, culminating in early April with the mercurial president threatening to fight China with suicide bombers if necessary. Much of his administration’s ire has been directed at China’s slow but inexorable annexation of Thitu Island, known as Pagasa to the Filipinos, which China has effectively seized by surrounding it with fishing boats piloted by paramilitary crews.

A spokesman for Duterte responded to the ABS-CBN report on the Scarborough Shoal at a press briefing Tuesday by accusing the Chinese of “performing acts of ownership” at the Scarborough Shoal that are “an affront to our territory and to our sovereignty.”

The Duterte administration remains reluctant to publicize details of precisely what it said to China in these diplomatic notes, or what legal action it plans to take. Duterte’s political opponents are hammering his passive approach to Chinese aggression and demanding firmer action. On Tuesday, an association of fishermen asked the Philippine Supreme Court to intervene and compel public officials to enforce environmental regulations around Scarborough and other shoals that would put a stop to Chinese clam harvesting.