Heavy monsoon rains in western India have caused at least three walls to collapse on to huts and city shanties, killing at least 27 people and injuring dozens of others.
At least 18 people were killed and 66 others injured after a 10-metre (35ft) wall demarcating an urban forest collapsed during the night in Mumbai, police officer Sunil Deshmukh said.
Rescue teams with sniffer dogs were searching the area afterwards, and rescuers from the Indian navy also fanned out to help rescue residents of the waterlogged city that is India's financial and entertainment capital.
Nine deaths were caused by two wall collapses elsewhere in Maharashtra state.
Six migrant construction workers were killed and five injured when a wall collapsed on their tin-roofed huts in Pune, an officer in the city's police control room said.
In Thane district, a school wall collapsed and fell on to huts, killing three people and injuring one, said a local civic official.
The monsoon season in India brings heavy rains from June to September that cause flooding and other damage.
Building collapses are common as the rains weaken the foundations of poorly built structures.
On Saturday, another wall collapse in Pune had killed 16 people living in a cluster of tin-roofed huts housing migrant workers and their families.
Monday's rains also flooded roads in Mumbai and waterlogged train tracks.
#MumbaiRain | Railway tracks at Sion submerged following heavy rainfall in Mumbai. Authorities have begun pumping out water at the station.— NDTV (@ndtv) July 1, 2019
For live updates, follow https://t.co/NOPdgizdSX pic.twitter.com/iZjsxGabvT
India's Central Railway said in a tweet that "nature's fury" made operating trains a "safety hazard" in some areas.
Trains were running at partial service today after thousands of passengers had been stranded overnight.
Millions of passengers commute daily on a network of famed railways in Mumbai.
The city has witnessed incessant rainfall over the past few days and floodwaters have entered homes.
A public holiday was declared for today and the Maharashtra government said only emergency services would be functional.
Maharashtra's chief minister Devendra Fadnavis tweeted: "People are advised to stay indoors unless there is any emergency."
BMC & @MumbaiPolice on continuous alert & working 24x7 to give all assistance to #Mumbaikars .— Devendra Fadnavis (@Dev_Fadnavis) July 2, 2019
As a precautionary measure & IMD advisory on heavy rains we declared holiday.
We need to remain alert for next 2 days.
My interaction with media on #MumbaiRains https://t.co/fFx5nYwyLu pic.twitter.com/LJLDMzPYq3
Weather officials said Mumbai had received the highest rainfall in a decade over a two-day period since Sunday.
TV channels showed footage of submerged cars and water flowing through ground floors of some residential buildings.
A domestic flight skidded off the main runway at Mumbai airport late on Monday night, and flight operations were partially restored today.
At least 50 domestic and international flights were diverted and another 50 flights have been cancelled.