An 11-story residential building under construction near Chennai in the southern Indian state of Tamil Nadu collapsed late Saturday, killing at least 11 people and trapping many others.
Most were construction workers who were seeking shelter during heavy rains and lightning.
Witnesses say about 50 people were in the building when it collapsed.
On Sunday, the chief minister of the state, Jayalalithaa Jayaram, said 31 people have been pulled from the rubble. "Out of them 11 are no more."
She said early indicators suggested builders had failed to follow building plans and had caused a structural defect.
Indian officials are questioning two people from the construction company.
Rescuers said their investigation could go on for days.
Analysts say loose regulations and inspections have contributed to a number of building collapses in India.
Earlier Saturday in New Delhi, 11 people died when their run-down apartment building fell to the ground.
Some information for this report was provided by AP, AFP and Reuters.