Unplanned roof fall discovered @ #3 entry,#2 northwest mains @ survey station 128, measured 20'W x 60'L x 11'H. The fall blocked secondary escapeway until the area was timbered off & life line was routed around the fall. Area was rebolted with 6' resin grouted bolts & 10'cable bolts. Brows on the inby/outby sides of the fall were supplement with 3 rows of 10' cable.