"The poachers killed the spotted deer in Belrayan range forests last night," forest sources said.
The poachers had an encounter with the field staff, but they managed to escape leaving behind their vehicle, they said.
The officials recovered the carcass of the spotted deer, a protected species under the Wildlife Protection Act.
"A member of the poachers' gang was arrested today and investigation has been ordered into the incident," chief conservator of forest and field director DTR Shailesh Prasad said.