"The ultras fired upon Kawasi Joga at his house in Dornapal town at around 8 PM," Sukma Superintendent of Police D Shrawan told PTI.
At least three Maoists stormed Joga's house, located near the stadium in Dornapal, around 450 kms away from here, and opened fire at him from a country-made gun before fleeing, the officer said.
Joga, who sustained bullet injuries on his stomach, was taken to a local hospital from where he was shifted to Bhadrachalam in Telangana for further treatment, the SP said.
A hand-written note was found from the spot in which Maoists have accused the teacher of acting as a police informer, he said.
Security forces have launched a search operation in the region to nab the attackers, he added.