Chaowalit Saeng-uthai, the district chief said an aluminium factory had illegally released the chemical substances into the canal. Public health officers were checking samples of the contaminated water before giving more details about the chemical substances.
Six cows were found dead after they had drunk water from the canal on Friday night. The cows convulsed and had froths and blood at their mouths.
The authority is also carrying out autopsies of the cows’ bodies to find out the cause of the deaths.