The killing was carried out by the Jharkhand Liberation Front (JLT), an outfit of the Communist Party of India-Maoist (CPI-Maoist), police said.
The JLT also left a pamphlet taking responsibility for the killing and warning other politicians of a similar fate if they continued to work against the Maoists, a police official said.
In another incident, maoist attacked the house of a Jharkhand Mukti Morcha (JMM) leader in East Singhbhum district on Friday morning. In the attack, a family member sustained bullet injuries.
Maoist are active in 16 of the 22 districts of the state. Nearly 750 people, including 290 security personnel, have been killed in the last six years in Maoist related violence.