Metro Manila (CNN Philippines, October 10) — At least 30 tubs worth of fish were found dead Thursday in the Las Piñas-Parañaque Critical Habitat and Ecotourism Area (LPPCHEA), police said.

The Manila Maritime Police Station said it discovered at around 9 a.m. “a large volume of dead fish” on the shoreline of Long Island. Fish species include sapsap, asuhos, bugaong, salinyasi, alacaac, banac and kandole.

Long Island is one of two islands that compose the LPPCHEA, a nature reserve south of Manila Bay declared to be a critical habitat in 2007 and recognized by the Ramsar Convention as a wetland of international importance as it plays a critical role in the survival of threatened, restricted-range and congregatory birds.

It is still unknown what caused the reported fish kill. Water samples have been collected from the area for testing.

The Bureau of Fisheries and Aquatic Resources has advised the public against consuming dead fish pending the results of their investigation.

It added that it will closely coordinate with the local government unit on the proper management and disposal of the fish.

CNN Philippines Correspondent Carolyn Bonquin contributed to this report.