13 Investigates uncovered startling information about a CSX freight car collision on the west edge of Downtown Indianapolis last week.

INDIANAPOLIS (WTHR) - 13 Investigates has uncovered startling information about a CSX freight car collision on the west edge of downtown Indianapolis last week.

Hearing the details, Indianapolis Fire Department Battalion Chief and spokesperson Rita Reith responded, "Oh my gosh, we are lucky nobody was killed."

The accident appeared to be a minor railroad mishap. However, radio traffic between railroad dispatchers, engineers and other CSX workers tell an entirely different story.

The seven freight cars that rammed a train engine head-on were uncontrolled runaways.

"They are already through the shed and going west," a worker said, sounding the alarm.

The first two cars rolled from the CSX State Avenue rail yard on the east side and headed toward the center of downtown.

"Is every one clear of the tracks? Yes. They just went by and they are going to start picking up speed the direction the are going," voices said on the radio.

The conversations and warnings follow the 3.5 mile journey as the cars barreled across the south side of downtown.

"They are picking up speed from where they're at right now," another worker warned.

The tracks cut through the southern edge of downtown, past Lucas Oil Stadium, the Indiana Convention Center, Victory Field and the Indianapolis Zoo.

"I need you guys to get out of your locomotives, it looks like we have a runaway car and get to a safe location," a dispatcher warned other approaching trains.

"I can see it coming around the curve, I am going to get to Harding Street and get the crossing blocked so nobody gets ran over," another worker said.

The collision occurred not far from the Harding Street crossing.

"How fast do you think it was going," a dispatcher asked. There was no immediate reply.

No one was hurt. Everyone was safe and by the sound of the radio conversations, relaxed, until about 5 minutes later.

"Emergency, emergency," someone shouted into their radio.

Five more rail cars, tankers, rolled out of the same CSX yard.

"Rollin' hot coming out on to the main right now, " came another warning. "Make sure you get out of there now, these cars are coming smokin'."

Down the same 3.5 miles of track, past numerous street crossings and populated city landmarks, the cars crashed into the already-wrecked cars ahead of them.

"I want everyone to stay away until we get haz-mat out there," a dispatcher radioed.

Fortunately, none of the cars, according to fire officials, carried hazardous materials.

During the 15-minute ordeal, CSX dispatchers apparently struggled to keep other trains clear of runaway cars, leaving engineers confused and frustrated.

"Precision railroading," one said.

"That's right, that's the new philosophy," replied another.

A CSX spokesman attributes the collision on human error, saying a worker did not apply an adequate number of hand brakes to the cars. Sources tell 13 Investigates safety mechanisms that prevent cars from rolling out of a rail yard were not installed until after the accident.