At least 10 people were wounded when a bomb exploded among a crowd of civil servants preparing to celebrate Indonesia's independence day in the Acehnese capital, officals said.

The wounded included two children, one of whom triggered the bomb when he rode over it on his bicycle, police said. Witnesses said a total of 13 people were hurt but the state news agency, Antara, reported 10 victims.

The blast occurred about 8am Saturday at Blang Padang field in Banda Aceh, the provincial capital. It was the most serious of numerous explosions and shootings which occurred throughout the capital and in the districts of Bireuen and North Aceh since Friday night.

In another incident, two police officers were wounded when a bomb exploded near their patrol in Banda Aceh Friday.

After Saturday morning's blast, a destroyed bicycle remained on the ground among a large amount of blood. Soldiers said they recovered many pieces of metal from the blast site.

Separatist rebels of the Free Aceh Movement called for a strike across the province Saturday.

In Lhokseumawe, home of ExxonMobil oil and natural gas facilities, public transport stayed off the streets and stores remained shut Saturday morning as residents stayed indoors, except for young boys playing soccer.

Soldiers and police were stationed throughout the city and also guarded a city field where police, soldiers and civil servants gathered to celebrate 57 years of Indonesian independence.

The government considers ExxonMobil to be a strategic national asset, and it is heavily guarded by troops.

GAM has been fighting for an independent state since 1976. An estimated 10,000 people have died during more than 25 years of violence in the energy-rich province on the westernmost tip of Sumatra island. An Acehnese rights body has said 845 civilians have been killed in Aceh this year alone.