One of them, Yong Ling Chow, 31, said the smoke, sometimes smelling of burnt rubber and heavy chemicals, has been blanketing the residential area almost on a daily basis for the past six months.

“Open burning had been carried out even before the haze situation got bad,” Yong told FMT.

Rawang assemblyman Chua Wei Kiat said the site where the open burning was being carried out was previously an illegal dumping ground sealed off by the authorities.

He said machinery on the land had also been confiscated.

Chua said the Department of Environment (DoE) and the Selayang Municipal Council had  been told to investigate the open burning.

“I will also talk to JPS (Department of Irrigation and Drainage) as the site is a river reserve,” he said.

Yong said the burning was carried out usually late at night or early in the morning but sometimes during office hours.

On several occasions, he said, residents had to call the Fire and Rescue Department when the blaze got out of control.

In a Facebook posting, he also said individuals had been spotted dumping large amounts of rubbish on the slope close to a stream.

“A majority of the population in Saujana Rawang is made up of young families, many with babies, toddlers and young children. We cannot continue to let them inhale such poisonous air on a daily basis,” he said.

Yong said Chua had informed the residents that he would discuss the matter with the relevant agencies tomorrow.

He said DoE had also agreed to look into their complaints but nothing had been done so far.