London police say the total number of people arrested at demonstrations around the G20 summit was 122. Many more were detained, however, amid violent clashes.Protesters have complained about the police method of preventing demonstrators from leaving cordoned-off areas, often for hours on end. Authorities maintain this was necessary for public safety, to stop the formation of breakway groups. Protesters also complain that some police were heavy-handed, failing to make a difference between peaceful protesters and other young people seemingly there just to provoke violence. Police are also still trying to confirm what caused the death of a man found lying on the ground at one of the protests.