No causalities are reported and no one was injured in the fire.
The fire broke out in the early hours in one of the houses of Sewri suburb, which later swept through other houses early morning on Saturday.
Shakeel, a local blamed the fire station for failing to reach the spot on time, which caused more damage.
"We were sleeping when we suddenly saw fire in one of the houses. We tried to douse it but it was in vain and it spread in the neighbouring houses as well. When I called the fire station the fire engines took long to reach the spot, which is why the fire spread even more.
(Q. How many houses have been burnt?)
"About 100 to 150 houses have been burnt," he said.
Wisps of smoke rose from the slum as locals rummaged through the ashes, trying to salvage their possessions.
According to local media reports, the cause of the fire was a short circuit but the police have not confirmed any reason so far.
"It is a slum area and there are loose electric wires. However, the reason of the fire cannot be ascertained yet. There are no causalities so far," said P A Dhoke, a senior police official.
Fire brigade officials said it took more than four hours to contain the blaze.
Fire safety regulations are lax, rarely implemented and not periodically reviewed in most small-scale commercial places, residential areas and firms across India
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