DHUBRI: Two persons (father and son) allegedly involved in the murder of Benu Chandra Rabha of Kochudola village under Kachugaon Police Station of BTC, were arrested by police on Monday. The accused persons are Dhruba Chandra Rabha and Bireswar Rabha. They were arrested with two handmade guns and barrel. They are now being interrogated. A police source informed that the duo shot dead Benu Chandra Rabha at his residence on the night of April 16 this year. Benu Chandra Rabha was killed in suspicion of being a witch and knowing black art. The police are also looking for a kabiraj (expert in black art), who had allegedly motivated Dhruba Rabha and Bireswar Rabha to kill Benu Chandra Rabha, source further informed.