The boy, identified as Akash Orang, was injured when the guard was trying to chase away a rhino at Mihimukh-Holmora area under Kohora Range of Kaziranga National Park (KNP), the police said.
Akash received a gunshot on his thigh and was immediately rushed to Jorhat Medical College Hospital after which he was referred to Guwahati Medical College Hospital, the police said.
Two Forest guards were suspended for the firing incident and they were Manas Borah, who handled the rifle when the incident took place and Anil Kalita, a KNP forest guard deputed at Mihimukh-Holmora camp, for illegally allowing Manas to handle his loaded his service rifle, KNP officials said.
Manas, who was new to Kaziranga, saw a rhino making movement near the KNP Park at Mihimukh point and picked up the rifle of Anil Kalita who was out from the camp for shopping, to fire and scare away the rhino, Barman said.
On thinking that the rhino might stray outside to the adjacent village, Manas tried to stop the rhino, but his finger touched the trigger of the loaded rifle and a bullet hit Akash, who is from the village and regularly visits the camp, the police said.