Waltham Fire responded on July 15th to 369 Main Street Cowboy Market for smoke in the building. Engine 2, 4, Rescue 1, Tower 1 and Medic 1 were dispatched. Engine 4 reported a light smoke condition and then said there was some fire. A working fire brought Engine 1. A second-alarm brought Squad 5, Engine 3 and Ladder 2. Firefighters were hampered because water could not be used with live wires. Firefighters had to be rotated out with 92 degree temperatures. Once utility services arrive an hour later, they were able to extinguish the fire. The Mass State Fire Marshal was requested.