Karbi Anglong superintendent of police B B Chetri told newsmen here that the gang leader Lyngdoh Rongpi was arrested from Jamelangshu hills last night and based on his interrogation his accomplices were netted at a village in Bokolia area today.
Two forest employees were also held on suspicion that they were also involved in killing the one-horned pachyderms, he said.
A huge amount of arms and ammunition including one AK-47 rifle, 37 rounds of ammunition, two 303 rifles and one gun were seized from them.
Chetri said the axe used to brutally hack to death of the poached animal for its horn has also been seized.
Rhino horn is highly valued across the world for its alleged aphrodisiac qualities and use in traditional medicine.
The killing of rhinos had created a furore in the state with wildlife lovers alleging involvement of top level officials and even ministers in it.