These pig farms were registered with the veterinary department on private land with agriculture land status, said Selangor executive councillor Hee Loy Sian.

He said the state government found that the polluted water flowed from the private land into the sea.

“Based on physical observation and sample reports, the water quality in the drains there was found to be polluted.

“Further investigation found the activities in the area only involved pig farming and oil palm plantation. Pig farming is suspected to be the culprit involved in polluting the drains,” he said in a statement.

Hee said the sampling exercise was conducted by the Selangor water management board, which had issued an order to the land owners instructing them to carry out repairs on the drains until the water quality is satisfactory.

The land owners were also instructed to carry out rehabilitation and repair works on the drainage outside their lots as well, he said.

Hee said if the owners of the premises fail to comply, a detailed investigation paper would be submitted to the public prosecutor for further legal action.

Earlier, a local newspaper reported that pig farming activities in the Tanjung Sepat area were causing local residents to face odour and water pollution problems for almost 30 years.