Rescuers have pulled a baby alive from the rubble of a building 11 hours after it collapsed in Mumbai, India's financial capital.

The infant was the 25th person to be rescued from the flattened five-storey apartment building.

A cheer went up from hundreds of onlookers as rescuers brought the baby out of a small tunnel in the rubble.

At least three people have died and rescuers are searching for dozens of others feared trapped.

It was the third deadly building collapse in six months in Mumbai, in a country where shoddy construction and lax inspections make such disasters all too common.

Relatives of the missing wailed and clung to one another, as heavy machinery lifted the largest slabs of concrete away. Dozens of rescue workers hacked away with crowbars at the flattened remains of what was once a five-story building.

Sixteen people were pulled alive from the building and rushed to a hospital, said Alok Awasthi, local commander of the National Disaster Response Force.

"Approximately 80 to 90 people are believed to be left behind in the building and trapped," Mr Awasthi said, indicating the death toll could soar higher in the coming hours and days.

The building collapsed just after 6 am near Dockyard Road in the city's southeast.

Mr Awasthi said that it was owned by the Brihanmumbai Municipal Corp, the city's municipal government, and that most of the people who lived in its 22 apartments were city employees.

Mumbai has already seen two similar disasters this year.

At least 72 people died in April when an illegally constructed building fell down, and in June, at least 10 people, including five children, died when a three-storey building collapsed.

Across India, buildings falling down have become relatively common. Massive demand for housing around fast-growing cities combined with pervasive corruption often result in contractors cutting corners by using substandard materials or adding unauthorised floors.