Lhokseumawe – Aceh provincial government has imposed an overnight curfew in the oil-rich but riot-torn district of North Aceh.

A statement issued Thursday in Lhokseumawe, the capital, bars people from leaving their homes between midnight and 4:30am.

"A curfew is being imposed in North Aceh because the security situation ... is getting worse as certain irresponsible gunmen are conducting unlawful actions," said the statement, signed by regent Tarmizi Karim and the local military and police chiefs.

Rebels from the Free Aceh Movement have been intensifying a campaign to set up a Muslim state in Indonesia's northwesternmost province by urging residents to boycott Monday's national parliamentary election.

Unidentified gunmen opened fire Thursday on a truck carrying ballot boxes in South Aceh, killing Abdul Gafar, a member of the local election supervisory council, and wounding the driver of a nearby bus.

A day earlier, an unidentified group burned down seven school buildings and a local government office in Lhoksukon, a town in North Aceh. The government has indicated the balloting could be delayed in the predominantly Muslim province.

Aceh, about 1,750 kilometers northwest of Jakarta, is one of three Indonesian provinces where separatist rebels are fighting for independence.

The others are the former Portuguese colony of East Timor and Irian Jaya, a former Dutch colony on the western part of New Guinea.

"We will wait to see the security situation over the next two days," Rudini, chairman of the General Election Commission, said Friday after meeting with President B.J. Habibie. He said a decision would be announced Sunday.

In the Aceh capital of Banda Aceh, five nongovernment groups, including two independent election-monitoring agencies, urged the government to cancel the election in Aceh.

"The election in Aceh would obviously trigger human rights violations against civilians," they said in a statement that claimed there are no security guarantees for voters or volunteer election monitors.