The clash erupted Wednesday after "Maoist cadres attacked policemen who were evicting Maoists from government-owned land they had occupied for the past five years," said Keshav Raj Sharma, an official at Bardiya around 500 kilometres (300 miles) west of Kathmandu.

He said that at least 17 people including seven policemen and several Maoist cadres were injured in the incident.

"The indefinite curfew was imposed to prevent any violence," said Sharma.

The Maoists have opposed the local authority's decision to station Armed Police Force personnel at a government-owned building in the area for security duty along the Nepal-India border, the official said.

The Maoists have had their army and weapons confined to UN-monitored camps, but continue to face accusations that they have not stopped using violence and intimidation.