One person died while another was gravely injured as the balcony on the second floor of a building, in southern part of the city, collapsed on Monday afternoon.

Seventy-year-old Kamala Chattopadhyay died while another 50-year-old woman, whose identity was yet to be confirmed, was badly injured when the balcony of an almost 40-year-old residential building collapsed at around 3.50 pm, when it started raining heavily, a senior police officer of Kolkata Police said.

Two fire tenders, teams of the Disaster Management Group besides, police were engaged in the rescue operation as a few more persons were feared trapped inside, he said.

"We are trying to locate if there are anybody else trapped inside," he said.

The injured woman is being treated at a private hospital.