Zamboanga has always been an edgy sort of place.

The former garrison town during Spanish and American colonial times lies at the tip of a finger of land pointing to the Sulu islands, a hotbed of Muslim resistance to Christian domination for centuries.

Earlier this month, officials were stunned to discover that the city's entire commercial district was on a list of hundreds of other areas in the southern Philippines that could be turned over to enlarge an existing autonomous region for Muslims under a peace deal with the country's main Islamic separatist group.

The majority of Zamboanga's population are Roman Catholic, the main religion of the Philippines, though the city also has a sizeable Muslim minority.

"The situation was unbelievable; it would have been like South Africa under apartheid," Zamboanga's mayor Celso Lobregat told me, reeling off landmarks that - on paper at least - could be partitioned in a Muslim enclave.

The homeland deal between the government and the Moro Islamic Liberation Front (MILF) is aimed at ending years of separatist fighting.

But it has rattled non-Muslim communities in the already volatile south. Suspension of the deal earlier this month by the Supreme Court, which stopped its formal signing, has provoked a furious response from the MILF rebels.

As it turned out, putting Zamboanga's commercial district on the homeland list was an error - nobody there is sure whether it was an administrative mistake or not.

But six smaller Muslim communities within the city limits have been included, and a similar configuration exists in other Christian-majority towns covered by the territorial agreement on Muslim domains.

The attempt by peace negotiators to keep the terms secret - not very successfully, it has to be said - has added to the climate of uncertainty.

The fallout from the suspension of the agreement has been severe. More than 30 civilians were killed in Monday's rampage by MILF rebels in mainly Christian towns in the provinces of Lanao del Norte and Sarangani bordering the existing autonomous region for Muslims.

Last week, rebels occupied several other towns and villages in North Cotabato province. It took the military four days of heavy air strikes and shelling to evict them. More than 160,000 civilians fled the fighting; many returned to find their homes destroyed.

The MILF's leadership insists that it did not order the attacks, which it blames on 'restless forces' on the ground angered by the stalled homeland deal.

"We are trying to pacify them," MILF spokesman Eid Kabalu told a local television network yesterday (August 19).

This is not the first time that a 2001 ceasefire has been broken. And it is not unusual for the authorities to also blame renegade MILF field commanders for violations rather than the rebel leadership, so as not to upset the peace process.

All the same, suspicions linger that the high command has sanctioned actions to prod the peace process along when it falters - as it so often does.

Filipinos may well have wondered about this while watching TV footage of bullet-ridden and machete-hacked bodies of civilians from Monday's mayhem.

There is also a danger of the situation being inflamed by angry and frightened Christians in rural areas organising themselves into armed groups. The reported burning of churches during last week's rebel attacks are a worry.

In a region awash with legal and illegal firearms, Christians and Muslims have been killing each other over land feuds for decades. Land, not religion, is really at the heart of this conflict, and clashes over religion are assiduously avoided here.

For that reason, there has been practically no sectarian violence since the early 1970s, when Christian and Muslim vigilante thugs attacked each other's villages.

Giving more territory to Muslims for self-rule will not be a straightforward map-making exercise where borders are simply redrawn. Enlarging the existing autonomous region will involve a patchwork of Muslim-dominated towns and villages dotted over a large swathe of the southern Philippines. Some areas, like in Zamboanga, could be in the middle of cities.

Opposition to the 'self-inflicted dismemberment' of the country, as one newspaper labelled the territorial deal, is growing in nationalist quarters.

At the end of the day, however, greater Islamic autonomy in the south will require the approval of Congress and referendums in the affected communities.

And even some Muslims are wary of joining an enlarged homeland that would supersede the existing Autonomous Region of Muslim Mindanao (ARMM), one of the country's poorest regions.

"Educated Muslims outside the ARMM know its bad record for public management and corruption," said Rey-Luis Banagudos, who promotes inter-faith dialogue for the Zamboanga archdiocese.

The Supreme Court justices began hearings last week to determine the legality of the homeland deal with the MILF.

But going by past rulings on urgent cases, it could take the court several weeks to deliver a ruling.

Philippine President Gloria Arroyo, meanwhile, is backing a resolution in Congress to change the constitution to adopt a federal form of government. Its author, Senator Aquilino Pimentel, believes an enlarged Muslim homeland with more self-governing powers could become one of 11 federal states that he is proposing.

That seems like a long shot. Proposals to amend the Constitution always spark superheated political rows here.

In the meantime, the peace process is in chaos, and the military has vowed to come down hard on the rebels involved in the attacks.

But neither side is likely to abandon a negotiated settlement to ending one of Asia's longest running separatist conflicts.

"Peace is the only option for us," affirmed Arroyo's spokesman Jesus Dureza yesterday. (ANN)