Angus Grigg – In less than two months, former Finnish President Martti Ahtisaari will rise in Oslo's City Hall and formally receive the Nobel Peace Prize. Norway's King Harard V will be there to see the peacemaker receive his medal, diploma and a cheque for $US1.5 million ($2.2 million).

It will be just recognition for a life's work, but the Nobel Committee must be nervous. That's because before Ahtisaari delivers his speech, Aceh, for which he was recognised along Kosovo and other trouble spots, might be less than peaceful.

The World Bank's Conflict Monitoring Update shows August was the most violent month in Aceh since 2005, when Ahtisaari's Helsenki agreement was signed. The rise in violence has been attributed to an increase in "political tension" as campaigning begins for next April's district, provincial and national elections. But this is not the full story. The World Bank said reports were circulating about a network of "rogue ex-combatants" looking to resume the armed struggle for independence.

"The level of support such groups command among the wider population and ex-combatants remains extremely weak," the bank said. "However, the potential exists for support to rise if those who come to power do not address the needs and grievances of the electorate."

But even without such threats, violence is certainly on the rise. The World Bank said the number of violent incidents was up 70 per cent in August, compared with the average monthly total for January to July. And there are growing concerns that foreigner organisations, which have previously been left alone, are being targeted.

The kidnapping of a World Bank consultant, a security guard from Save the Children and seven Chinese nationals working in the private sector has alarmed observers. Such worries were exacerbated by a grenade exploding at a Save the Children office in May and repeated reports of violence between former members of the Free Aceh Movement (GAM).

These incidents appear to have won the Australian government's attention. The Department of Foreign Affairs is known to be considering raising the travel warning on Aceh, which currently recommends exercising "extreme caution". To raise the warning would cause the Rudd government and Australia's Ambassador to Indonesia, Bill Farmer, a few headaches but it may also be prudent.

In a report released last week the International Crisis Group also warned about the dangers of pre-election violence in Aceh. "Aceh is politically vibrant but on edge," the report says.

"Many people in Jakarta and the international donor community have declared Aceh a success and turned to other matters," said Sidney Jones, a senior adviser with the Crisis Group.

"But complacency is misguided – the tensions are palpable and need to be addressed." Jones made her comments before the Nobel Committee awarded Ahtisaari the Peace Prize, but she could easily have been referring to them. From the Crisis Group's perspective mistrust appears to be the biggest problem.

They say the Indonesian military (TNI), which controlled the drug and illegal logging trade in Aceh during the years of conflict, is worried about Partai Aceh, GAM's political wing, winning control of local legislatures and challenging Jakarta's authority.

Partai Aceh, for its part, is said to be worried about overt or covert interference from Jakarta. Smaller parties are worried about intimidation by Partai Aceh, which sees itself as the natural party of government. To make the situation a little more complex the current governor, Irwandi Yusuf, is reportedly not well.

The former GAM leader with an unparalleled ability to keep the ex-combatants in line is thought to have suffered a slight stroke in August. This has not been confirmed but his cooling presence and support for the peace process are seen as vital for stability in Aceh.

But like most conflicts this one is also about money. In many areas of Aceh, former GAM fighters have come to operate like mafia, involving themselves in extortion and protection rackets.

Those on the ground say much of the violence revolves around control of these illegal trades, but there are fears the increasing level of violence will provoke a response from the TNI.

So far the upsurge in violence is being handled by the police but there is little doubt the military would like to move back in and take control of its old businesses.

Such an action would certainly broaden the conflict. On the positive side, however, GAM's supreme commander, Hasan DiTiro, came out strongly in favour of the Helsinki agreement when he returned to Aceh over the weekend.

Hasan, who was has lived in self-imposed exile in Sweden for last 30 years, made it very clear he was committed to the peace process. But the 83-year-old has little control over GAM these days and some believe his presence in Aceh may actually stoke the fires of independence.

All these negatives in Aceh are not designed to take away from Ahtisaari's lifetime of achievement. He did, after all, halt a war which raged for 30 years and killed 15,000 people, but as has been proved the world over, it's always dangerous to declare a separatist movement dead.