SINGAPORE - A burning smell in north-east Singapore is likely related to a fire at the Tanjong Langsat landfill in Pasir Gudang, Johor, the National Environment Agency (NEA) said.

The agency told The Straits Times on Sunday (Feb 17) that it received nine feedback cases on the smell between Friday evening and 11pm on Saturday. Eight of them were received after 6pm on Saturday.

Several netizens living in Yishun, Ang Mo Kio, Sengkang and Hougang also reported a "smoky" or "smoggy" smell on social media.

Reddit user blahhh87 said he "thought of doing some late night cycling but decided not to".

Facebook user Benny Ong wrote: "It smells really bad."

The feedback cases come just over a week after reports of a burning smell in several parts of eastern Singapore, including Tampines, Bedok and Pasir Ris, on Feb 8.

The source of that smell was due to a fire at a landfill in Bandar Tenggara, in south-eastern Johor, the NEA said at the time. It received 31 cases of feedback then.

On Sunday, the NEA said the Department of Environment Johor had updated the agency that while the fire at Bandar Tenggara landfill had been put out, there was another fire at the Tanjong Langsat landfill in Pasir Gudang.

"It is likely that the burning smell detected in the north-east of Singapore is related to this fire," said an NEA spokesman, who confirmed that the agency had not been able to trace the smell to any local causes so far.

The spokesman added that the prevailing winds, which have been blowing from the north-east, are expected to persist for the next few days.

At 11pm on Saturday, the PSI at the North, East and Central regions ranged from 42 to 48, in the "good" range.

The one-hour PM2.5 readings in those regions ranged between 6 and 12 micrograms per cu m (mcg/m3), which is in the "normal" range. PM2.5 is the dominant pollutant during haze episodes.

The NEA also said that the levels of ambient volatile organic compounds remain within safety limits.

In contrast, at one point during the episode on Feb 8, the one-hour PM2.5 readings rose to the "elevated" range of 46 to 62 mcg/m3. The PSI also hit 65 at a separate time that day.

The NEA said it would continue to monitor the air quality and provide updates, should there be any change in the situation.