An early morning explosion Wednesday woke the marsh foreman for Searles and Son Marsh as fire broke out in a 4,900 square foot building. The building, a combination of maintenance shop and warehouse, was burning heavily and partially collapsed when firefighters arrived on scene at 3864 Searles Road, Cranmoor, about 10 miles west of Wisconsin Rapids, Vesper Fire Chief Dennis Dederich said. The building contained an acetylene torch, LP gas cylinders, fork lifts, fuels and other things people would expect to find in a maintenance shop, Dederich said.