The incident happened on Thursday when supporters of ousted Shahzadpur Municipality Awami League president Abdur Rahim (VP Rahim) and those of the party unit's Organisational Secretary and Mayor Halimul Haque Miru were involved in a violent face-off, police said.
Daily Samakal Correspondent Abdul Hakim Shimul came in the line of fire and was rushed to Shaheed Ziaur Rahman Medical College Hospital in Bogra bullet injuries in his head.
Head of neurosurgery department Dr 'Sushanta' said, "The injured journalist has received a bullet in the head. Nothing can be said about his condition before 72 hours.
"If he is shifted elsewhere in this condition, it may be harm him. So he cannot be shifted elsewhere for better treatment."
Protesting against the incident, he said, his supporters blocked the Bogra-Nagarbarhi road.
Mayor Miru said supporters of Rahim attacked his house following a fight between his younger brother Pintu and Rahim's brother-in-law.
When the attackers opened fire, he admitted to firing blanks himself to try to 'bring the situation under control.'
Journalists unwilling to be named said 15 others besides Shimul were injured.
Shahzadpur Police Station OC Rezaul Haque said the road blockade was cleared within half an hour and that one person was detained in connection with the incident.
Police officer Shahanur Alam has said Pintu has been "shown arrested" in the case.
Shahzadpur Sadar remained tense following the incident. RAB and police personnel have been deployed to keep law and order.
Journalists took out a protest rally in the evening and demanded punishment of the mayor.