The minors -- Sahidul, 10, Safikul, 9, and Lalsun, 12 -- had apparently entered the drain after they saw some glass bottles, but got caught in the sludge. When Hasidul, 26, and Afsae Ali, 30, tried to rescue the kids, they, too, were trapped.
As soon as the locals came to know of the incident, they informed the cops who helped pull them out of the drain.
"They were taken to Rao Tula Ram Memorial Hospital in Jaffarpur. The doctors declared them brought dead," Deputy Commissioner of Police (DCP) Surender Kumar said.
The fire department had also sent a fire tender, but they could not save the victims. Preliminary investigation suggests that the five persons might have drowned after fainting due to extreme heat and gas inside the drain, the police said.
When NDTV reached the spot in southwest Delhi, the family was inconsolable after losing five members to that drain.
"My brother's kids and my son had gone looking for scrap, and one of them came back with the news that they had drowned... My husband and brother rushed to rescue them... But no one returned alive," said Hasina.
Twelve years ago, the Assam floods had forced Hasina and her family to migrate to Delhi. All of them collected waste and made about Rs 3,000 at the end of three months.
Hasina doesn't have the time to mourn as the rent of their jhuggi is due. The little money that the family had saved was used to perform the last rites. She will have to get back to work as soon as possible and she will cross the same drain again...
Sanjay Jhakar, resident of the area, said repeated complaints have been made to the authorities but no efforts have been made to close the drains.
A case has been registered in the matter and the police will send a notice to the Public Works Department.
(With inputs from agencies)