to gain a more definitive answer but we want the public to know that we are doing everything in our power to what happened during this fire. reporter: last monday s fire destroyed 404 baltimore street and the businesses inside and damaged several others. but the atf says it needs to find out q-úwhat touched off t fire. the fire was so intense that it collapsed a part of the wall behind the building. investigators say to determine what caused the fire they literally had to dig vvwit out. imagine filling four roll back dumpsters big roll back dumpsters by hands with shovel full at the time. that s basically -2zpá happened it was an effort by a lot of guys that worked 8, 10 hour days, 7, 8 days in a row, and really brutal conditions. it has been with 1wñthe assistance of citizens who have stepped forward that has brought us to this point in the investigation. their information has proven instrumental in corroborating what the fire scene has revealed to us. but out ther