At least 30 people were injured yesterday during a post-poll violence involving supporters of two rival councillor candidates at Bahirgola Bazaar in the district town. Local residents said an argument was going on between defeated councillor candidate Shahadat Hossain and elected councillor Shahadat Hossain over the announcement of election result. As a sequel to the feud the two groups attacked each other with machetes and brickbats, leaving 30 people injured. The injured people have been admitted to Sirajganj Sadar Hospital and different clinics. Of them, condition of two persons is stated to be serious. Police brought the situation under control.