The protests have erupted in a country which only recently saw an end to ten years of civil war between government forces and Maoist insurgents.

The violence flared as authorities lifted a curfew yrsterday in three towns in the Terai region and maintained it in two others, including Birgunj.

"Protesters are trying to break the curfew by burning tyres," Shambhu Koirala, chief district officer told AFP from Birgunj.

"Some protesters pelted stones (at police) and tried to burn two police posts in the town. The situation is tense and there are reports of clashes between police and demonstrators but no arrests have been made," he said.

The protests began after a teenage boy was shot dead on January 19 during a fight between Maoists and activists belonging to the Mahadhesi community which is demanding greater political representation.

Mahadhesi leaders have said the group accounts for a third of impoverished Nepal's 27 million people and that the Maoists are over-represented in the nation's new parliament.

The parliament was set up after the Maoist rebels and coalition government signed a peace deal to bring the rebels into government.

The Mahadhesi dominate the Terai plains region, known as Nepal's bread basket, and have long complained of discrimination by highland communities.

The protests, which began in Lahan Bazaar town and spread into four other towns, became ethnic clashes after the Mahadhesi began attacking people from the hill regions.

Nepal's Prime Minister Girija Prasad Koirala has called on the group to begin talks and the Mahadhesis have urged him to name a date.

On Friday, Koirala met with Maoist chairman Prachanda to seek a way to settle the unrest in the Himalayan nation.

The group organising the protests has warned that unless Nepal's government addresses their complaints, the violence would continue.

Nepal's Maoists have said pro-royalists are involved in the protests and are trying to undermine the peace process which has left King Gyanendra facing dismissal.

The UN chief's personal representative to Nepal's peace process called Friday for an end to the violent protests and said such bloodshed could disrupt crucial elections due to be held later this year.