Lakhya Dutta, a KMSS executive committee member, was waylaid this morning at Borkul on National Highway 37 here by four persons and severely assaulted, police said.
The four also warned Dutta to refrain from any agitational activities in future, police said.
A seriously injured Dutta has been admitted to the Jorhat Medical College where his condition was stated to be stable.
Dutta has identified Choy Das, a Youth Congress local leader, and three others for their alleged involvement in the attack.
The attack on Dutta comes less than a week after six Youth Congress members assaulted Gogoi, a Team Anna member, in Lower Assam's Nalbari district.
Gogoi, who received head and back injuries, was released on Monday after three days in the hospital.