The incident happened near Raghai bridge in the Minapur police station area, they said.
Four men, riding two motorcycles, started indiscriminate firing at Yogendra Kumar, killing him on the spot when he was on the way to Patna after attending the wedding of his niece at his native village, an officer said.
Kumar was a resident of Naka Derma village in the East Champaran district, he said.
He used to deal in sand and stone chips.
Kumar’s family members, who were accompanying him, took him to the Sri Krishna Medical College and Hospital (SKMCH) where the doctors declared him dead.