New Delhi: With drones deployed for surveillance, polling began on Sunday in the fourth and penultimate phase of the Bihar elections involving 55 assembly constituencies, including 12 affected by Maoists, in the state's flood-prone belt.

As many as 1,47,39,120 lakh voters are eligible to decide the fate of 776 candidates in fray in 55 of the 243 assembly constituencies spread over Gopalganj, Siwan, West Champaran, East Champaran, Sheohar, Sitamarhi and Muzaffarpur districts.

Paramilitary forces have been deployed at all polling booths and drones would be used for the first time for surveillance, officials said.

The Election Commission has ordered sealing of the international border with Nepal and while security forces in the districts bordering Nepal are on alert.

(IANS)