)
Balloting takes place Saturday for Left ruled Tripura's second Lok Sabha seat.
The state's electorate voted for the other seat Monday.
Over 1.13 million voters - half of whom are women - are eligible to exercise their franchise to choose their Lok Sabha member from the tribal reserved Tripura East Lok Sabha constituency from among the 12 candidates, including two women.
"As Tripura shares borders with Bangladesh (856 km), Assam (53 km) and Mizoram (109 km), tight security measures have been taken in the mountainous Lok Sabha constituency. Helicopters would be pressed into service to oversee the polling," state Chief Electoral Officer Ashutosh Jindal told IANS.
The Border Security Force (BSF) has mounted heightened vigil along Tripura's boundary with Bangladesh, most parts of which are still unfenced and porous.
"We have deployed additional troopers along the Bangladesh borders to prevent the trans-border movement of the inimical elements during the electioneering period," BSF's chief spokesman Bhaskar Rawat told IANS.
On April 7, over 86 percent of the 1.2 million voters cast their votes in the Tripura West constituency.
The CEO said that of the 1,490 polling stations spread across the Tripura East parliamentary constituency, 18 polling stations have been categorised as hyper-sensitive and 252 sensitive.
In Saturday's polling, the main battle will be between Jitendra Choudhury of the Communist Party of India-Marxist and Sachitra Debbarma of the Congress.
Choudhury is Tripura's industry, commerce and rural development minister, while Debbarma is a National Award winning teacher.
Others in the fray include Parikshit Debbarma (Bharatiya Janata Party), Bhriguram Reang (Trinamool Congress), and Karna Bijoy Jamatia (Aam Aadmi Party).
Since 1952, the Left has won the Tripura East seat 10 times while the Congress secured it five times. The CPI-M has been winning the seat uninterrupted since 1996.
Former chief minister Dasaratha Deb of the CPI-M (1993-98) won the seat four times while the party's central committee member Bajuban Reang was elected from the constituency a record seven times.
