A highway overpass under construction in southern India collapsed Sunday, killing at least 20 people, police said.

Several people were believed still trapped in the rubble after the accident in Hyderabad, the capital of Andhra Pradesh state, local police chief Balwinder Singh told reporters.

The overpass was being built to connect the city's posh Banjara Hills residential neighborhood to Panjagutta, a busy commercial area in the city, CNN-IBN television reported.

Cranes and ambulances were rushed to the accident site, the Press Trust of India news agency reported.