Gogoi, who had gone to Punni village in Dharmapur area of the district to take stock of the flood situation, was allegedly attacked with sticks and other sharp weapons, the police said.
Gogoi filed an FIR at the Nalbari police station alleging that the attack was carried out by six youth Congress activists at the behest of Assam Agriculture and Parliamentary Affairs Minister Nilamani Sen Deka who represents Dharmapur assembly constituency.
Gogoi, who is also the Secretary General of Krishak Mukti Sangram Samiti (KMSS), received head injuries.
A profusely bleeding Gogoi was admitted to the Nalbari Civil Hospital in a critical condition.
The police have launched an investigation into the incident, the sources added.