Security forces and Maoists exchanged gunfire near Kendua Pahari under Dhanwar Assembly constituency in Giridih district on Tuesday.
No casualty was reported in the encounter that took place just an hour before polling began at Dhanwar from where former chief minister and JVM (Prajatantrik) president Babulal Marandi is contesting, additional Superintendent of Police Kunal Kumar said.
The rebels opened fire at the security forces but in the strong retaliatory action by the security personnel the ultras fled into the forest, he said.
The encounter that began at 6am lasted for about 15 minutes and occurred under Gaona police station limits, Kumar said. Polling is going on peacefully at Dhanwar.