At least 30 people were said to have been injured when blocakde supporters locked in clashes with law enforcers in Natore Sadar upazila Wednesday noon.
Witnesses said Jatiyatabadi Chhatra Dal and Jubo Dal brought out a procession in Kanaikhali area around noon when police intervened.
Police said the blockade supporters blasted at least four crude bombs when the clash began. BNP claimed they were attacked by police.
Law enforcers lobbed seven teargas shells and fired 14 rounds of rubber bullets to tame situation, Sadar police Officer-in-Charge Aslam Uddin said.
Natore BNP General Secretary Aminul Haq calaimed at least 30 opposition supporters were injured during this time.
He said among those injured were Natore JCD Vice President Sanwar Hossain, Shechwashebak Dal VP Morshed, and BNP assistant Organising Secretary Nasim Khan.