The figures are based on initial reports, according to Anupam Srivastava, head of the National Disaster Response Force (NDRF).
Three NDRF teams are on their way from the city of Pune to the city of Mahad in the Raigaid district, where the five-story building collapsed, Srivastava told CNN.
The teams are expected to reach the site in the early hours of Tuesday morning local time (5 pm ET), when they “will have a better idea of the situation,” he added.
The southwestern state of Kerala has been plagued this season by rain and flooding. At least 43 people, including three children, died earlier this month after torrential rains caused a landing.
Monsoon rains have caused deadly floods in the eastern Indian states of Assam and Bihar since May, affecting more than 2.4 million people, flooding large parts of a national park, and killing more than 100 wildlife, including a dozen rhinos.
Elsewhere in the region, Nepal has sustained massive landslides and severe floods, while nearly one-third of Bangladesh – and a fifth of its population of 161 million people – have been affected by floods.
Emma Reynolds, Helen Regan and Swati Gupta of CNN contributed to this report.
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