Polling began on Wednesday morning in 12 Lok Sabha constituencies in Bihar amid tight security.
Long queues of voters were seen at several polling centres much before the polling started.
Shoot-at-sight orders have been issued against the booth-grabbers if the lathi charge failed to quell them while trying to vitiate the polling.
Over 100 companies of the central para-military forces besides home guards and district armed police personnel have deployed to ensure a free and fair poll.
Indo-Nepal borders connecting the constituencies of Purnea and Araria have been sealed to prevent the anti-socials and Maoist rebels from creating disturbances during the poll.
Of 14,370 booths spread over the constituencies, 5,847 have been declared super-sensitive and 4,339 have been identified as sensitive, official sources said.
The constituencies where the poll began in the final phase are Madhepura, Purnea, Saharsa, Araria, Kishanganj, Katihar, Bhagalpur, Balia, Khagaria, Begusarai, Munger, and Banka.
Around 1.49 crore voters are eligible to participate in Wednesday's exercise to decide the electoral fortunes of 133 candidates, including politicial heavyweights like RJD boss Laloo Prasad Yadav, his bete-noire Union Consumer Affairs minister Sharad Yadav, Union Textile minister Syed Shahnawaz Hussain and Union minister of state for External Affairs Digvijay Singh.