Another rhino was killed by poachers at Kaziranga National Park in Assam on Saturday with the toll rising to seven at the UNESCO World Heritage site.
There was heavy exchange of fire between a group of five poachers and forest guards near Sundari Camp of the Park's Burapahar range around 6 am, KNP sources said.
The guards then recovered the carcass of the bullet-riddled rhino with its horn intact, they said.
The poachers, however, fled away after the encounter.
This is the fourth rhino to have fallen victim to bullets of poachers this week.
On January 29, a rhino was killed and its horn sawed off near the Hatibandi Camp under Bagori range of the Park along Nagaon and Karbi Anglong districts.
The same day another rhino was killed and its horn removed by poachers near Borholla camp in the Burapahar range of the Park.
In the third incident on January 30 poachers killed a rhino when it was being escorted back by forest guards to KNP after it had strayed to Majuli the night before.
Concerned over the increased incidents of rhino poaching in the state, the CID has taken over the investigation of seven cases related to poaching and supervising another four cases, official sources said.
The government also termed the frequent incidents of poaching of rhinos as "a conspiracy of certain forces with vested interest".
It also said that "the alleged nexus of some insurgent elements with poachers" would also be probed into.
"The state government has already moved the central government to institute an enquiry by the CBI to unearth any such conspiracy. Any conspiracy to endanger wildlife will be dealt with firmly," it said.
The government said it was committed to conservation of wildlife conservation and had taken a slew of initiatives in this regard.
Meanwhile, the forest department in a major crackdown on Thursday suspended two officers, show-caused two others and removed three home guards for 'dereliction of duty' in connection with the recent killing of two rhinos in Kaziranga National Park.