The young man leaped in front of me waving a huge, rusty cutlass and shouted "For Jesus!". He ran to join his friends in a rousing chorus of 'Onward Christian Soldiers', sung in Indonesian, as they pressed up against the line of police officers, who were nervously fingering their guns.

Jonathan Head reports from the scene of disruption in Ambon

Just 50 metres away were their neighbours, the Muslims.

Wearing white bandanas inscribed with verses from the Koran, they were whipping themselves up into a frenzy, shrieking and groaning in front of the line of soldiers trying to hold them back. Some drew their own equally menacing weapons across their stomachs, a macabre miming act of disembowelment, a gesture of undiluted religious hatred.

A thick pall of smoke rose from the Muslim quarter, obscuring the green hills which crowd around the city. The atmosphere was explosive.

Something had to give.

Many Christian villages have been razed to the ground

It came with a crackle of gun-fire, driving back the Christians in panic.

One young police officer, fresh out from another Indonesian island, marched screaming towards the crowd, firing his revolver into it. He was restrained by his colleagues.

The Christians scooped up the bleeding bodies of their friends from the road, and shouting curses at the police, bundled them into cars to take them to the hospital.

Famed for spices

No-one in Ambon seems to know what's gone so wrong on their island. Once it was famed for the spices which hundreds of years ago brought European and Arab traders to its shores.

They left behind a patchwork of religions - first Islam from the Arabs, then Catholicism from the Portuguese, then Calvinism from the Dutch. The Ambonese mixed them with their own traditional beliefs - and they developed an unusual system of alliances between villages of all faiths, called Pela Gandung.

It superceded the potentially divisive issue of religion because it bound Muslim and Christian villages to help each other in times of trouble. It worked for centuries. It certainly isn't working now.

Tight security has not prevented more than 140 deaths

Ambon is tiny - little bigger than the Isle of Wight. But travelling anywhere has become something of an expedition, because no-one is willing to go without an armed guard.

Even the shortest journey requires crossing both Christian and Muslim roadblocks - as a result ordinary cars drive around with guns poking from their windows.

The three police officers escorting us to the north coast seemed nervous - perhaps because they were all Christians, and we were heading into Muslim territory, perhaps because their rifles looked old and not entirely trustworthy.

Razed to the ground

But it became easier to understand their apprehension once we got out of the city - village after village had been razed to the ground, most of them Christian.

Many Muslim immigrants flee to other parts of Indonesia

In one place the blackened walls of what had once been a church stood just a few metres from the remains of a mosque.

In the pretty village of Hila, Indonesia's oldest church was nothing more than a pile of rubble, along with the surrounding houses. The Muslim village head explained that the mob had come from elsewhere - he pointed back into the forested hills - but he could not explain how it had known exactly which houses to attack, leaving the Muslim homes untouched.

In truth this is an ugly conflict about territory and identity.

Attitudes have hardened

Attitudes on both sides have hardened - each believes the worst of the other. Muslims accuse Christians of planning an independent Christian state, Christians believe they will be left a powerless minority by the thousands of Muslim immigrants who have come to Ambon.

Destroying houses is simply a crude method of trying to change the percentages.

The Ambonese are famed throughout Indonesia for their singing. Every day glorious sounds drift out of the church which dominates the city centre.