A group of about 40 persons, who trade illegally in sand from the banks of the Brahmaputra, were returning in two boats from Nagarberra area after midnight when they were stopped by local residents who allegedly demanded money from them.
The traders refused to pay, following which the residents handed them over to the forest personnel of West Kamrup Forest Division.
The traders allegedly attacked the residents and the forest employees and three forest guards were seriously injured.
The injured were admitted to the Guwahati Medical College Hospital.