FORT WAYNE, Ind. (WANE) – It was a typical summer day in the Summit City that quickly turned dark.

On July 20, 1973, A Penn Central train was making its way through Fort Wayne heading eastbound at about 42 miles per hour when 10 train cars derailed from the main line of a double track railway near Thomas Road, according to documents from the U.S. Department of Transportation. The train consisted of 11 cars and three locomotive units.

Eight of the train cars were contained with hazardous materials, but two cars that were part of the derailment contained vinyl chloride, a toxic chemical used to make plastic products.

At around 3:45 p.m., two cars separated from the rest of the train, causing the emergency brakes to be applied. The car with vinyl chloride was punctured about four feet from the center of it causing the chemical to leak, where it caught on fire and then exploded.

Shortly after first responders arrived at the scene, they ordered residents in the area to evacuate around 4 p.m. and extended through the rest of the night.

About 3,000 people within a two mile radius near the accident were evacuated from their homes and businesses.

Officials determined the cause of the accident to be from a broken coupler, the part which connects the train cars together, on one of the cars.

The coupler dropped down to the tracks and derailed the train when the braking system and axle could not pass over the coupler.

Another one of the train cars containing vinyl chloride had its safety valve released due to the intensity of the heat from the fire and led to more of the chemical being leaked.

This continued for hours after the derailment and around 7:22 p.m. the second car exploded. No casualties were reported at the time and and three train cars were damaged in total. Six cars sustained significant damage while one experienced minor damage.

A home in the area caught on fire and was destroyed after being hit with debris from the explosion.

The total cost of the damages was more than $99,000, which is more than $667,000 in 2023 when counting for inflation.

One local firefighter was on duty that day and recollected what occurred then. Bruce MacPherson, a retired firefighter with the Southwest Fire Department, was working for what was then the Wayne Township Fire Department. He said the fire had burned for about 7-8 hours after the derailment.

“I remember when the tanker car exploded, you could feel the ground shake and the shock wave it sent throughout the area,” MacPherson said.

When the tanker car exploded, pieces from it hit a house causing damage and eventually set the home on fire, destroying it entirely. The fire department has a piece from the tanker car on display in its training building and a sign from the train tracks.

He said when they were evacuating residents from the area, they were sent to Time Corners Shopping Center.

“Most of the people cooperated with us. We would drive down streets blaring our sirens and speaking into the vehicle PA system for people to exit their homes. We would also knock on their doors asking them to evacuate,” he added.

At the time of the fire, firefighters were unsure of what type of chemical leaked from the tanker car. Hose lines were set up as long as 800 feet to take out the fire.

Firefighters at the time did not have the safety standards they do today. An example of this was firefighters not having to wear oxygen masks and wearing jackets made of rubber, where now their jackets are made of Kevlar.

MacPherson said it took them about 4-5 days to get the train cars back onto the tracks.

“We do training sessions regarding train derailments today and how to prepare for them if it were to happen again,” he said.