Residents living in parts of Chembur, Wadala and Ghatkopar woke up on Thursday morning to see thick smoke cover large parts of their locality. The smoke was later learned to be on account of a fire which broke out at the Deonar dumping ground at 3am.

Almost 12 hours later, authorities managing it were finding it difficult to bring it under control. The fire was on the Ghatkopar side of the 132-acre dumping ground.

A senior civic official at Deonar said, "From Thursday morning the smoke started to affect residents of Mankhurd, Govandi and Chembur severely. "
Meanwhile, lower night temperatures and higher pollution levels ensured that Mumbaikars woke up to heavy smog on Thursday morning.

The city's air quality index deteriorated to the poor category. When air quality is poor, people with heart or lung diseases, older adults and children should reduce prolonged or heavy exertion.