Patrolling forest guards came across the bullet-riddled body of a male mature rhino near Kawoimari forest camp in Bagori range of the Park this morning, they said.
The forest guards also found two .303 rifles and several rounds of ammunition from the spot, they said.
A massive search operation with sniffer dogs has been launched in the area to nab the poachers, they said.
This is the ninth incident of rhino being killed in the Park since January this year.
Meanwhile, a walkathon was organised by Kaziranga University in association with Assam government's Forest department as a part of the campaign to stop poaching of one-horned rhinoceros.
Also, forest guards found two .303 rifles from Bishwanath Bhola Chapori in Sonitpur district. The two rifles were found in the jungles near the northern bank of river Brahmaputra, a part of Kaziranga National Park's sixth addition, forest officials said.
The arms recovered today was suspected to have been used by poachers who killed a rhino and removed its horn in the Park's western range, where two rifles and several rounds of ammunitions were already recovered.
A massive search operation was on to nab the poachers who were suspected to have escaped to the northern side of the Park, sources added.
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