A large number of houses were inundated in Hulimavu here as water from a lake flooded the area on Sunday after its bund was damaged, officials said.
Efforts were on to shift around 250 families badly affected by the sudden flood which also swept away several cars and two-wheelers, they said.
City Mayor M Gautham Kumar said the incident occurred when some people allegedly tried to lay a pipe with the help of an earthmover and the civic body BBMP would investigate about it.
About 250 families had been affected and efforts were on to shift them to safety and provide food, he told PTI.
The Bruhat Bengaluru Mahanagara Palike (BBPM) officials the fire and emergency services personnel were carrying out the relief work.
Pumps were deployed to flush the water out of basements of residential complexes, while efforts were on by engineers in the civic body to plug the breach, officials said.