 At Burntollet an Ulster loyalist crowd numbering in the region of 300, including 100 off-duty members of the Ulster Special Constabulary (USC), attacked the civil rights marchers from adjacent high ground.Stones transported in bulk from William Leslie's quarry at Legahurry were used in the assault, as well as iron bars and sticks spiked with nails.Nearby members of the Royal Ulster Constabulary (RUC) did little to prevent the violence.