After midnight, a series of small fires were discovered on the pier. Some guards fled, fearing an explosion. Others attempted to fight the fires and eventually called the Jersey City Fire Department. At 2:08 am, the first and largest of the explosions took place, the second and smaller explosion occurring around 2:40 am. A notable location for one of the first major explosions was around the Johnson Barge No. 17, which contained 50 tons of TNT and 417 cases of detonating fuses. The explosion created a detonation wave that traveled at with enough force to lift firefighters out of their boots and into the air.