The Maoists also set ablaze several vehicles in three separate incidents in the district bordering Chhattisgarh.
The extremists of Communist Party of India (Maoist) struck after midnight. They shot at P Jogaiah, former Maoist, who died on the spot in Veerapuram village.
Maoists also opened fire on another person at Suryanagar in Bhadrachalam town in the same district. M Ramesh, also a former Maoist, escaped with bullet injuries on his hand.
Police said they were attacked as Maoists suspected them to be acting as informers for police.
The Maoists also burnt down four trucks, two JCBs and a tractor at Bhupatiraopet in the same district.
They abducted two workers from one of the trucks but later released them.
About 40 to 50 Maoists, who had reportedly crossed over from Chhattisgarh, carried out the attacks after forming three teams.
Following the attacks, police sounded an alert in the area and launched combing operations.
Telangana was once the stronghold of Maoists but their activities have been brought under control by sustained police operations.
Police claimed that in 2017, Maoist violence declined by 90 per cent.
Director General of Police M Mahender Reddy said in December 2017, that the police were maintaining the vigil, especially in areas bordering Chhattisgarh to foil any attempt by Maoists to regroup.