IT STARTED as a good-natured march in which tens of thousands joined a protest on a bright Baltic sunlit day. People sang, danced and proudly waved their banners.

Within hours their demonstration demanding stronger action by the G8 on climate change, Aids and poverty had been turned into a cynically manipulated operation to ensure that news about the summit would henceforth be dominated by scenes of water cannon, tear gas and stone throwing.

The early stages of the march were peaceful, with people from all over Europe parading through Rostock’s streets and little sign of any police presence. There was a carnival atmosphere of singing, chanting and banner waving.

I was heading for the city’s harbour with a group of good-hu-moured British campaigners when we noticed an outbreak of violence in the crowd ahead of us. It had evidently been organised by the Black Block, a group of black-clad trouble-makers whose sole aim was to goad the police.

It’s Grrrrr8 (honest)

As the G8 summit begins in Germany, Hugo Rifkind explains everything you need to know – and lots of stuff you don’t

Multimedia

• Video: Our young man in Heiligendamm

• Audio: Behind the scenes at the G8

• Pictures: G8 summit

BACKGROUND

• Quotes: what Putin told The Times

• Blair reinvented the Middle Ages

• The West is starting this Cold War

• Save the planet: give to China

Related Internet Links

• Official site of the G8 summit Heiligendamm

Officers who had been observing the march by the side of the road pulled down their visors and ran to help colleagues confront an increasingly volatile crowd. We saw rocks being thrown. Then the rioters started to pull up pavement slabs and throw them at the police lines. The crowd became frightened. People sought shelter anywhere they could from the flying missiles.

At that point Guy Taylor, a veteran British protester, noticed that the police were getting ready to charge. “It’s always an ominous sign when police start to put on their riot gear,” he said.

The police ran towards the rioters and then pulled back. As they withdrew, members of the crowd shouted insults.

Meanwhile, the programme of songs and speeches from a protest stage continued. There seemed to be two separate protests running alongside one another - one innocent, the other chillingly aggressive.

As violence raged at one end of the harbour, the more peaceful body of the protest continued at the other, with the crowd cheering on fiery speeches delivered from the main stage. Bands also took to the platform, including Tom Morello, the former guitarist of Rage Against the Machine.

Among the beer and hot dog stands surrounding the stage, legitimate protesters, including several from Britain’s Stop the War coalition, were indignant that the real messages would be lost by the actions of a few rabble-rousers. But the speakers on the main stage, apparently oblivious to the flying stones and the fires, railed against the police for “provoking” protesters.

To prevent the situation getting out of hand the police decided to withdraw for 45 minutes. The atmosphere grew calmer, but only briefly. Then we saw thick black smoke pouring into the sky as some demonstrators, almost certainly the Black Block again, set fire to a car parked in a disabled slot a few streets away.

Suddenly the police returned with a vengeance and started to fire tear gas canisters towards the crowd as they attempted to get a fire engine through to the burning car. Black Block protesters started to hurl stones at the firemen. To push them back the police brought up a water cannon.

The peaceful elements in the crowd – by far the majority – could smell the acrid tear gas sweeping across the harbour area. The march organisers appealed for calm over loudspeak-ers as ambulances started to arrive. Many in the crowd started to run away. There was a sense of panic and disappointment. In contrast, some young protesters clearly relished the battle. I heard one shouting: “Isn’t this great!” as his friends hurled stones at policemen.

By early evening the atmosphere was becoming extremely ugly. The organisers had given up any pretence of continuing the protest from the stage and many people who had joined the march with high hopes earlier in the day had fled.

One young boy, bleeding and with his head covered in bandages, was stretchered past me. The air was filled with the stench of tear gas, petrol fumes from the burning cars and smoke grenades thrown by protesters. Someone saw a petrol bomb being flung at a water cannon.

The stone throwing was particularly alarming as rocks were falling at random - the hard core who wanted to spark this trouble clearly cared little about who they hit.

As the streets began to clear, the police surrounded the most violent groups, their arms linked together in a chain to ensure that none would escape. Anyone who tried to make a run for it was swiftly dragged to the ground by officers.

By the end some demonstrators were shouting: “This is another Genoa,” a reference to riots at the G8 meeting in Italy in 2001 at which one person died and many were injured.

Among the peaceful demonstrators with whom I spent much of the day the mood of disappointment was bitter. Those who had been intent on pursuing a legitimate protest by peaceful means were forgotten. The scene had been set for further anarchy and bloodshed in the days ahead.

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