Battalion 2 Chief arrived on the scene and reported flames showing with debris littering the entire intersection of 13th and Allen. A second alarm was immediately requested.
Engine 10 was instructed to approach from the west end of Allen Street and drop a line into the scene. After securing a supply they were directed to start hitting the fire. Engine 9 was directed to grab a hydrant at 15th and Liberty Street. Engine 4 approached from 13th and Tilghman Street.
Heavy fire was found throughout the remnants of the destroyed houses and was rapidly spreading down the row. Crews were hindered in fighting the fire due to electrical hazards. To the rear of the building, an officer reported approximately 30-40 power lines down and live. It was then recommended to use master streams or the whole block would be lost.
A 3rd alarm was requested by command along with Lehigh County units to relocate to the City stations for standby. Engine 13 responded as RIT and Truck 2 was directed to 13th and Allen to set up for master stream operations.
Engine 4 reported seeing fire coming from underneath the sidewalk which was believed to be fueled by underground gas lines. Engine 4 and command agreed that due to the close proximity of the Gross Towers to the burning gas, the elderly living complex should be evacuated. A level three MCI was declared and the resources for the evacuation of 350 people were requested.
The fire continued to burn out of control and spread throughout the row. Engine 10 requested to ladder the rear of the building and trench the roof, but command denied the request due to structural damage seen throughout the row. Units reported doors being blown out of units in the middle of the row and declared that no one was to enter the building.
Since the gas was still leaking, the fire continued to burn out of control. Resources from the Lehigh County Special Operations Team were requested along with a response from the Eastern PA EMS Council.
Due to the frigid temperatures, firefighters from Lehigh County were summoned to the scene along with off-duty Allentown firefighters to relieve first-in crews. Whitehall Engine 3711 and Lower Macungie Engine 3011 responded into the scene to assist.
After hours of searching for the source of the gas, UGI was finally able to control the leak and the bulk of the fire was knocked down around 4:00 a.m. By this time it was too late, the fire had spread throughout the entire block.
Once daylight broke, the damage could be seen more clearly. Two homes had been completely demolished by the explosion, and six had been destroyed by fire. The search for the deceased began with the assistance of cadaver dogs.
In all, five people perished in the explosion ranging in age from four months to 79 years old.
Crews remained on scene throughout the day and some utility crews could still be found on the scene days later.