A RADICAL splinter group of environmental activists is plotting to invade Heathrow’s main runway today and stop flights. If they are successful they could cause chaos for holidaymakers.

An undercover investigation by The Sunday Times revealed the scheme, drawn up by about 20 protesters and led by an activist claiming to be a former soldier. Hundreds were given training last week at the camp for climate action on how to cut through fences and tunnel under security barriers.

The plot - condemned by police and airport executives for potentially endangering lives - is not sanctioned by the main organisers of the camp who are planning high-profile protests today around the airport periphery.

Senior police officers will be alarmed by plans for a runway invasion. Exposure of the group’s intentions may now lead the activists to pick a new target.

The “mainstream” camp events planned today include a mass demonstration at the headquarters of BAA, the airports operator, which is based on the Heathrow perimeter. The demonstration is scheduled to end on Tuesday.

Further protests are planned at petrol stations and McDonald’s outlets in the Heathrow area. Campaigners are also threatening to target Royal Bank of Scot-land in the City of London. They have been instructed to put bicycle locks around their necks and attach themselves to buildings and each other, forming a “human octopus” to make it more difficult for police to arrest them.

More than 2,000 people are estimated to be at the camp, set up last Sunday just north of Heathrow. More than 1,000 police are on duty this weekend to ensure that the country’s busiest airport remains open.

Protesters were arrested yesterday after breaking into Agrexco UK, an Israeli fruit and vegetable importer near Heathrow. Amos Orr, the general manager, said: “A lot of them were drunk. They broke doors, spread papers everywhere and they were very aggressive. They were singing about Hamas.”

Seven campaigners were also charged with causing criminal damage after supergluing their hands to the doors of the Department for Transport headquarters in London on Friday.

The aim of the protests is to draw attention to the impact of flying on climate change. The plans for potentially illegal direct action were announced at a meeting on Friday night attended by a Sunday Times reporter posing as an environmental activist.

During the meeting one protester, who claimed to be a former soldier, appealed for people to stage a demonstration on Heathrow’s main runways. The man, in his forties, said: “I’ve got detailed maps of the area, including the runways. On Sunday we can get on them and make our point.”

The meeting’s organisers told him that it would be “too dangerous” to break onto the runways, but a group of 20 protesters agreed to join him and discuss the plan after the meeting.

In the past week mini “action camps” were held where protesters were given training in how to conduct “espionage” on potential targets, scale fences and walls and the best methods for attaching themselves to buildings.

A leaflet was handed out giving instructions on how to deal with CS spray and charges from riot police. It said: “The best form of defence of all is CHAOS! If a situation changes constantly they simply cannot keep up.”

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