ANTI-G8 PROTESTERS who had been at the centre of yesterday's clashes with police outside Gleneagles, were stunned into silence by the news of explosions in London.

Protest organisers called emergency meetings at the eco-camp near Stirling to inform the huge crowd, who had been surrounded by a police security cordon to prevent further violence.

Around 1000 people staying at the camp immediately put down their musical instruments and placards and gathered into huddles.

Hundreds of protesters tried to use their mobile phones to contact loved ones in London, while others discussed how police in the area would respond to the blasts.

Maxim, a Russian anarchist from the radical Dissent network, said: "All of a sudden, the various groups called everyone together and they announced the terrible news. Everyone was shocked and appalled. Some people sat down in disbelief, others were worried about friends in London and tried to contact them.

"There is no party atmosphere here anymore. There is no sound apart from the police helicopter, and we are just gathered in small groups discussing the horrendous nature of today's events.

"What has happened is truly awful and it cannot be connected with our protests in Gleneagles, but there is also a tense feeling in the air - we don't know if the police will be more heavy-handed with us now."

Dozens of police officers in riot gear had cut off the campsite as a "security measure" early this morning. The ring of force remained in place when news of the London blasts filtered through, but the situation remained calm.

Police chiefs said they had ordered the cordon in the interests of public safety amid fears that more violence was likely to erupt today in Stirling and Gleneagles.

Officers were allowing protesters to come and go as long as they submitted to body searches.

Senior police sources have reportedly criticised Stirling Council for allowing protesters to camp in Stirling in the first place. They said it provided 200 to 300 violent anarchists with a base from which to attack the summit.

A police spokesman said the mood at the campsite early today, however, was "calm" and that no arrests had been made overnight. But protestors said many campaigners were left feeling frightened last night when police moved in. They say the police action has only served to be provocative and was curtailing their civil liberties.

One protestor said: "I don't think there were any plans inside the camp for violence in the first place. This is just provocative."

Another member of the eco-camp added: "People become very frightened when they're penned in. The police have caused so much pressure. There's a lot of harassment going on of people here."

Police said they had made 91 arrests yesterday following violent scenes in Stirling and seized several weapons including an axe, a machete and a high-powered catapult with ball-bearing ammunition. Eight officers were injured in the clashes. Central Scotland Police said they were taking the action in an effort to avoid a repeat of last night's violence when protesters poured out of the camp and clashed with officers as they went on a spree of vandalism.

"Officers have been willing to facilitate peaceful protest and will continue to do so," a police statement said. "However, a violent minority who have no interest in peaceful and lawful protest brought widespread disruption to the community of Stirling yesterday and the force believes that a repeat is planned.

"Police have no plans to enter the campsite and everyone within is urged to remain there for the time being in the interests of safety Anyone wishing to leave the site peacefully with no intention of causing disorder can do so with the assistance of police officers."

Officers are speaking with protesters about the security operation, he added.

Vehicles, banks and a Burger King restaurant on the Springkerse retail park in Stirling were attacked yesterday.

The centre of the town was closed, as was the M9 at the Granada services after it was blocked by protesters. Rail services were also disrupted for a time, with a confrontation between police and protesters at Stirling and a temporary blockade of the rail line north of Dunblane. Five police officers needed hospital treatment after the attacks near the camp.

Around 120 protesters were due in court today following G8-related clashes with police. A total of 191 people were arrested yesterday - 65 in the Stirling area, 26 in Edinburgh and 100 in the area covered by Tayside Police.

Of these, 65 are due to appear at Stirling Sheriff Court, 30 at Perth Sheriff Court and 26 at Edinburgh Sheriff Court. Those remaining will appear in the next few days.

Tayside Police said that 91 protesters were arrested following incidents in South Perthshire yesterday.

Chief Constable John Vine said that his officers were "prepared to handle whatever comes our way" as the world leaders begin talks at the G8 summit. "I'm very pleased with how the operation has gone so far," Mr Vine said. "We were well-tested yesterday but our plans held firm. I think our officers behaved professionally and were very restrained in the face of violence. We're not complacent, though. We know this event will attract violent anarchists and we're prepared to handle whatever comes our way."

Meanwhile, anti-war protesters have locked themselves to the entrance of an engineering company they accuse of profiting from the war in Iraq.

Five demonstrators are preventing workers from entering Weir Pumps Ltd in Glasgow.

A spokesman for the group, which arrived at around 7am, said: "We are protesting against the fact that the company is profiting from the war in Iraq. We are preventing people from getting in - they are just standing outside at the moment. We'll be here as long as possible. "

The group was also present at Monday's demonstration at the Faslane submarine base.

They have chained themselves together outside the building in the city's Cathcart area, preventing anyone from entering the main gate of the building.

They have put up a banner that says "making a killing" and are handing out leaflets to passers-by. Strathclyde Police confirmed that they were in attendance.

Weir Pumps was previously targeted by protesters in December. It designs and manufactures pumps for the oil, water treatment and gas industry.