Mumbai - Eight people were killed and at least 15 were missing on Wednesday after the heaviest monsoon rains in a decade breached a dam in the western Indian state of Maharashtra, authorities said.
In the state capital Mumbai, the death toll from a wall collapse in a slum on Tuesday following the torrential downpour reached 24, with more rain expected in coming days.
Heavy rain continued to lash the coastal city of 20 million people Wednesday, bringing it to a virtual standstill as flooding cut train lines, closed the airport's main runway and caused traffic misery.
Building collapses and dam breaches are common during the monsoon in India due to dilapidated structures that buckle under the weight of continuous rain.
India's National Disaster Response Force (NDRF) told AFP they were using drones over the area flooded by the breach of Tiware dam, around 275 kilometres (170 miles) from Mumbai.
"We have located eight dead bodies and over 15 people are still missing," said spokesman Alok Awasthy.
Police teams and government officials were also helping rescue efforts.
In the state capital, a spokesman for the local authority said the death toll from the wall collapse in a slum in the north of the city had risen to 24, with many others being treated for injuries.
Six labourers also died in the nearby city of Pune when another wall collapsed.
India's weather department has warned of "extremely heavy rainfall" in parts of Mumbai in coming days.
After more than 100 flights were either cancelled or diverted from Mumbai airport on Tuesday, officials announced the operations on the main runway were still closed.
According to Skymet Weather, a private-weather tracking agency, Mumbai faces serious risks of flooding with more than 200 millimetres (eight inches) of rain expected in the next few days.