The accident occurred when the bus, carrying a total of 47 passengers, was coming to Vikasnagar from Hanol, official sources said.
The vehicle skidded off the road and fell into the ditch, they said.
Sixteen bodies have so far been recovered from the ditch.
The injured are being rushed to various hospitals of the area.
Senior administrative officials have rushed to the spot and search and rescue operation has been launched.
The cause of the accident was not immediately known.