Around 26 tons of fish raised in cages on the Cai river in southern Vietnam have died since Tuesday allegedly due to pollution in the water, local authorities said Thursday.
The Dong Nai Province's Department of Natural Resources and Environment and other related agencies took water samples in An Binh and Thong Nhat wards, and Hiep Hoa Commune, where the fish had died.
They suspected that some companies had released untreated waste water to the river during recent heavy rains.
Scientists are now testing the samples for contamination.
Between June 7-12, over 54 tons of domestic fish also died on the Dong Nai River due to pollution, said Nguyen Ngoc Hung, chief inspector from Dong Nai's environmental department.
However, authorities have yet to find companies illegally discharging untreated waste water, according to Hung.
The department has proposed that provincial authorities order the environmental police department to check all waste water release sites along the Dong Nai river.