A ground-plus-three-storey building located in Fort area of south Mumbai collapsed on Tuesday night, a senior fire brigade official said.
Three to four persons were feared to have been trapped under the rubble while a couple of people were rescued, he said.
"'Yousuf' building in Lohar chawl on Mangaldas Road suddenly collapsed around 9.15 pm," the official said.
It was a 'cessed' building under the jurisdiction of state housing agency MHADA, as per the preliminary information.
Fire brigade jawans and personnel of the Brihanmumbai Municipal Corporation were on the spot and search and rescue operation was on, said an official from the BMC's Disaster Management Cell.
"As a precautionary measure, adjoining Dwarkadas building and remaining part of the Yousuf building have been evacuated," P S Rahangdale, chief of Mumbai fire brigade, said.