Agartala/Aizawl, April 3 (IANS): Nearly 80 percent tribal refugee voters, living in Tripura for the past 17 years after fleeing from their villages in Mizoram, voted by postal ballots for the Lok Sabha polls in Mizoram, officials said Thursday.

Balloting for the lone Lok Sabha seat in Mizoram, bordering Myanmar and Bangladesh, will be held April 9.

"Around 80 percent of the 11,500 Reang tribal voters have cast their votes through postal ballots during the past three days. The voting is still in progress in six of the seven relief camps," Tripura Chief Electoral Officer Asutosh Jindal told IANS.

Balloting began Tuesday under the close supervision of the Election Commission.

Jindal said : "Tight security measures have been undertaken in six of the seven relief camps, where facilitation centres were set up to enable the eligible refugee voters to cast their votes by postal ballots."

He added that the poll panel had appointed seven observers to oversee the electoral process at these centres.

About 11,500 of the over 36,000 Reang tribal refugees, locally known as "Bru", living in the Kanchanpur and Panisagar refugee camps of Tripura for the past 17 years, are listed in Mizoram's electoral rolls.

Five NGOs and youth organisations, led by the Young Mizo Association, have been organising protest rallies in Aizawl and other places in Mizoram since last week demanding that the poll panel revoke its decision to take the refugees' votes through postal ballot.

Mizoram Chief Minister Lal Thanhawla, who is also the state Congress president, had earlier this month urged Chief Election Commissioner V.S. Sampath not to allow the refugees to vote through postal ballots.

The tribals fled their villages in Mizoram and took shelter in Tripura in October 1997 after ethnic trouble with the majority Mizos over the killing of a Mizo forest official.

About 5,000 refugees returned to their homes in the past three-and-a-half years following continued persuasion by Mizoram, Tripura and union home ministry officials.