A man and a 10-year-old boy were killed when a slab and part of a parapet of a five-storey under-construction building in Mumbai collapsed, police said. Municipal Corporation officials gave this information on Monday.

A civic official said the incident took place at Kailash Business Park in Vikhroli area at 11.10 pm on Sunday.

It is noteworthy that there was heavy rain in some parts of Mumbai on Sunday night.

When fire brigade personnel reached the spot after receiving a call, they found that part of the parapet and slab had collapsed, while parts of the under-construction building were hanging, the official said.

"Firefighters removed the structure that was in danger," he said.

Before the fire brigade arrived, some locals rushed the 38-year-old man and the boy to Rajawadi Hospital, where doctors declared them brought dead, the officer said.

Earlier on June 5, one person was killed and another was injured when a large part of the slab of a single-storey building collapsed in Mahim area here.

The India Meteorological Department (IMD) announced the onset of southwest monsoon in Mumbai on Sunday, two days ahead of the normal time.

After heavy rain on Sunday, there was waterlogging in many parts of the city including Vikhroli.