EMPLOYEE CLAIMS THAT HE BEGAN HAVING BACK PAINS AFTER HE HELPED UNLOAD 50 50 LB BAGS OF EXPLOSIVES FROM A TRUCK TO A MAGAZINE. HE CLAIMS HE HELPED UNLOAD THE BAGS AROUND 8 AM AND STARTED HAVIN G PAINS ABOUT 12 PM. HE WAS SEEN AT PRO-MED CLINIC AND RELEASED TO LIGHT DUTY. HE STATES HE DID NOT HAVE SEVERE PAIN UNTIL HE WOKE UP THE NEXT MORNING.