The driver of the speeding Assam State Transport Corporation (ASTC) bus lost control of the vehicle in the Adabari area following which it overturned and rolled down the road to fall into a pond at around 3.30 pm.
The locals have been assisting the police and local administration in the rescue operation.
Seven bodies, including those of three women, have been recovered from the accident site while 21 others with serious injuries have been rescued and sent to hospital.
Police said there were around 50 passengers in the bus when the accident occurred and there is a possibility that some could still be trapped inside.
The bus was on its way to Barpeta from Guwahati via Mukalmua.