JOHOR BARU - About 15 students from a religious school in Pasir Gudang district in Johor suffered breathing difficulties and vomiting, possibly due to exposure to poisonous gas on Thursday (June 20).

Pasir Gudang Fire and Rescue Station chief Ibrahim Omar said they received a distress call about the incident at Sekolah Agama Taman Mawar at 3.39pm, reported The Star.

"When we arrived at the scene, we found about 15 students suffering from such symptoms, and five of them have been sent to Sultan Ismail Hospital for further medical treatment," he said.

A hazardous material team was sent to the school.

Malaysia's Health Minister Dzulkefly Ahmad told reporters at a news conference in Putrajaya that "the symptoms look like a possibility of poisonous gas or one of those volatile organic compounds as the cause... just like the Sungai Kim Kim incident".

The toxic pollution of Sungai Kim Kim resulted in over 4,000 people falling ill and led to the closure of 111 schools in Pasir Gudang in March.

Datuk Seri Dzulkefly said his ministry is closely monitoring the situation and "everything is under control", reported Bernama news agency.

He added that they have yet to decide whether to close the school temporarily.

Meanwhile, Johor Health Department director Selahudden Abdul Aziz said the department was investigating the cause of the illness.

"Once we discover the main cause, we will be issuing a statement on the matter," he said.