Dahal sustained minor injury in the incident, according to the police.
Dil Bahadur Lama (29), of Parsa district, who is one of the assaulters, surrendered to the police right after the incident.
Eyewitnesses said the attackers were six in numbers and they had come on three motorbikes. One of the pillion riders opened fire on Dahal.
Five others involved in the incident are absconding. Police said they have intensified search for them. Police said the reason behind the attack is not known yet.
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