Polling began on Saturday morning for the bypoll to Bikramganj Lok Sabha constituency in Bihar amid shoot-at-sight orders against booth grabbers.
The borders with Jharkhand and Uttar Pradesh have been sealed to check the entry of trouble-makers, Rohtas District Magistrate and Returning Officer for the by-election Vishwanath Singh said on Saturday.
A little over 13.11 lakh voters will exercise their franchise at 1,436 polling stations, 607 of which have been declared sensitive and hyper-sensitive, he said.
Around 4,000 men and officers of central para military forces are assisting the district police and special auxiliary police to ensure free, fair and peaceful polling, Singh said.
The by-election to the seat has been necessitated by the death of sitting JD(U) MP and chairman of NAFED Ajit Kumar Singh in a road accident in August this year.
Though 12 candidates are battling it out for electoral laurel, the contest is mainly between JD(U)'s Meena Singh, wife of Ajit Kumar Singh, and RJD's Ashok Kumar Kushwaha.
The BSP has fielded Baliram Mishra, while the CPI-ML has put up party's MLA from Karakat, Arun Kumar Singh.