The rebels slit the throat of Mukkali Gundu Rao near Kumkumpudi village under GK Veedhi Police Station limits of the district on Sunday night, Superintendent of Police Koya Praveen said.
They left behind a note near his body saying Rao had associated himself with the anti-Maoist wing of district police and shared information with cops about Naxals and their activities, he said.
Rao was husband of former Mandal Parishad Territorial Constituency member M Chandrakala and was engaged in the business of supplying tiles in construction sector.
Police have filed a case and launched an investigation to identify the Maoists involved in the murder.