Are Aceh rebels spreading their wings?

An elite special forces soldier guards a shopping mall after a small blast close to army headquarters in Jakarta

JAKARTA, Indonesia (CNN) -- Rebels from Indonesia's troubled of province of Aceh, fighting for independence from the republic, are believed to be extending their armed struggle to the capital Jakarta after they were linked to a series of bomb blasts here in the past month.

In early July, eight people were injured in a bomb blast at a mall owned by the Indonesian special forces Kopassus. The mall was located less than two kilometres (1.2 miles) from Kopassus' headquarters.

On June 9, Jakarta was rocked by two explosions -- one outside a discotheque which seriously wounded two people and another at the Jayakarta Hotel.

Police recently arrested five Acehnese in several locations where they also found grenades, homemade bombs, detonators, 20,000 rounds of ammunition and 160 magazines.

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The separatist Free Aceh movement (GAM) denied the charges, saying the accusation was an attempt by the government to justify imposing martial law in Aceh which would give the military total control in running the province.

"All the Free Aceh soldiers are in Aceh. No order has been given for any men to be assigned outside of Aceh," Free Aceh spokesman, Teuku Kamaruzzaman, told CNN by telephone from the provincial capital of Banda Aceh.

"Our targets are in Aceh as we only fight in the area which is in dispute with the Indonesian government," Kamaruzzaman added.

Kamuruzzaman also denied that the five arrested men were GAM members, saying his organization did not know the suspects.

On Monday, local internet news service, Detikcom, quoted one of the suspects, Syahrul, as saying he was not a GAM member.

Activists of the Central Information for the Aceh Referendum at a rally in Jakarta marking International Anti-torture Day

Intelligence sources in Jakarta told CNN that GAM was planning to stage low-level guerrila warfare in the city and had six targets, which included the national police headquarters and national electricity firm, PLN.

"They have been planning this for many months but it is only now that they managed to obtain explosives to conduct it," said the source.

"However, they don't have powerful weapons. They are mostly low-level explosives and home-made bombs but this is enough to terrorise the population," the source added.

With the seizure of the cache of explosives over the weekend, the intelligence officer said part of the rebels' strength has been paralysed.

Gam has been fighting for independence in the staunchly-Muslim, resource-rich province since 1976.

Vast resources

The province has grown restive through the years as they perceive Jakarta as plundering Aceh's vast natural resources while giving little in return.

In an attempt to ease separatist tensions, the government gave Aceh special autonomy and greater revenue-sharing of its natural resources but to no avail. Several dialogues have been held between GAM and the government but they failed to bring peace to the province.

The death toll in Aceh is huge with thousands killed and thousands more displaced from their homes as the fighting often resulted in homes and schools being razed to the ground.

The debris of a burned down school in Aceh, where violence continues in spite of a cease-fire

Last year, some 2,000 people, most of them civilians, were killed in fighting between Gam and security forces, according to the Brussels-based International Crisis Group.

Human rights groups estimate about 600 people have died this year alone.

Top Security Minister Susilo Bambang Yudhoyono flew to Aceh on Tuesday for a week-long trip to assess the situation and said the government would decide next month whether or not to proceed with dialogue or take tough action, including imposing martial law.

Martial law or military emergency, will place the running of the province under Aceh's military commander.

Terrorist label

Yudhoyono also called the rebels "terrorists," a label vehemently opposed by GAM who regard it as a move to gain U.S. support for its operations against the rebels by linking it to the global war on terrorism. (Full story)

Human rights activist are against martial law, saying that past military operations had only resulted in the death, torture and rapes of thousands of innocent civillians.

"Thousands of people were killed, tortured, raped or gone missing during the 1989-1998 military operations. If martial law were imposed, it would only bring immense suffering on innocent civilians," said Ori Rachman of the Commission for Missing Persons and Victims of Violence (Kontras).

The local press have reported that many young male Acehnese were fleeing the province in recent days as they fear being caught in the crossfire between GAM and the military should martial law be declared.