Unplanned roof fall in return on 1st left panel off of #8 belt in #8 entry. Fell from #10 Brk to 11 1/2 Brk (134' long X 8-10' high X 18-20' wide) between spad #2373 & 2384. No injuries, no equipment involved, no ventilation affected, no travelway affected. Date of development 6-29-2010.