Police said about six goons surrounded 70-year-old Yadav, a former minister, when the procession was near the district collectorate and beat him up injuring him seriously.
Yadav was on way to submit a memorandum to the district officials demanding ban on sale of liqour, the police said adding he was rushed to a hospital for treatment.
Senior Superintendent of Police (SSP) of the district, Rajesh Kumar said strict action would be taken against those responsible for assaulting the RJD leader and investigation was on to identify the culprits.
Various women groups have been agitating in Muzaffarpur district over the past ten days demanding ban on sale of liqour and cancellation of licences of the vendors.
