Eyewitnesses said Suresh and Hira were asked by the neighbouring society residents to clean the choked drainage pipes near Upasana building. When Suresh climbed down the 12-feet deep manhole he was caught in a sudden current of silt while toxic gases suffocated him and he became unconscious. Alerted by the commotion below his companion Hira too stepped inside to try to save him, but fell victim to the overpowering gas and died in the manhole.

Later, another labourer Sanjay noticing the open manhole approached it. No sooner he reached the opening, he too was hit by the strong smelling gas and collapsed. A bystander saw the unconscious Sanjay and tried to wake him up.Meanwhile, the Bhayander fire brigade was informed at about 3.25 pm. Of the six firemen, five were absent. The lone firemen presentwas engine driver Neelkanth Mhatre who rushed to the spot and removed the two bodies with the help of locals. The incident took place at about 2.30 pm and the police arrived at the scene at about 5.15 pm. Eyewitnesses said Suresh was a resident of the Bangladesh slum in Bhayander (west) while Hira stayed in Jogeshwari.

Rajkumar Kamble, Sanitation Inspector of the Mira-Bhayander Municipal Council rushed to the site after hearing rumours that two of the MBMC staff were drowned while cleaning a culvert. He stated that the manhole is a junction for sewage drains.