Renowned environmentalist DV Girish and his colleagues were assaulted by drunk youths at Bhadra Wildlife Sanctuary Monday in Chikmagalur district.
The Indian Express reported the accused passed lewd comments at a woman colleague of Girish and when he protested, the team was attacked.
The police lodged a complaint on Tuesday.
Girish and his team managed to escape from the spot but the accused chased them on their bikes.
Villagers who came to know about the incident eventually came to the rescue of Girish and his team.
The police are yet to make any arrests in this case.