Passers by noticed the damaged statue in Ambedkar Nagar area in the morning and a crowd soon gathered there demanding immediate arrest of those responsible, police said.
They said the group started throwing stones and damaged several vehicles passing through the area and also tried to set fire to a few parked there.
They stalled traffic alleging that the statue was deliberately damaged though police said it might have been an accident.
The Kakadeo station house officer said a new life-size statue of Ambedkar would be installed in place of the broken one and a search was on for those who might have damaged it.
Police was deployed in Kakadeo area and the situation was under control, he said.
