PERSON WAS WATCHING LONGWALL SUPPORTS ADVANCE, #126 SUPPORT DID NOT ADVANCE ON AUTOMATICE AND PERSON WENT TO #120 SUPPORT TO CATCH PRIME BUTTON. THE PANLINE WAS ADVANCING AND WHEN IT DID THE RELAY BAR BOLT ON PANLINE AT #126 SUPPORT BROKE. THE BOLT STRUCK PERSON AT #120 SUPPORT IN THE LEFT ANKLE.