Hundreds of anti-poverty protesters were driven back from the Gleneagles estate by riot police with dogs late on Wednesday after they breached the 6ft-high steel security fence that surrounds the G8 summit venue.

About 300 protesters had broken away from a 3,500-strong crowd of protesters marching through the nearby village of Auchterarder. They crossed a field and briefly breached the so-called “ring of steel”, pulling down a 20ft section and throwing rocks at officers who had been flown in by a Chinook helicopter.