The assailants stormed into the wholesale grocery shop of 62-year old Jhumurmal Jain and opened fired at his neck and chest. He died on the spot.
The local people managed to catch one assailant identified as Mohd Islam and handed him over to the police, but the other one managed to escape.
The police recovered a pistol from the assailant.
Meanwhile, the All Assam Bhojpuri Parishad has called a Dhubri bandh tomorrow, while another business association has called an indefinite strike in the district from today demanding immediate arrest of the other killer.
AIUDF, the main opposition party in the state assembly, has extended its support to the bandh.