BARI, Italy – A major head-on collision between two regional trains in southern Italy Tuesday morning has left at least 20 people dead and dozens more injured.

The two passenger trains were on a single-track line at the time of the collision, between the coastal towns of Bari and Barletta, and the crash left the carriages crumpled accordion-style.

“I think there are many dead,” says the commander of the local fire department, Riccardo Zingaro. “There was a head-on collision on a single-track. Some coaches are completely crushed and rescuers are pulling people from the wreckage; there are also many wounded.”

Each of the trains was formed by four wagons, and the first two wagons of each train were the hardest hit. On impact, the carriages buckled and pieces of sheet metal were scattered dozens of feet around the countryside in the area of the crash.

Firefighters continue pulling people from the wreckage, including a small child who had to be airlifted to hospital.

The cause of the collision has yet to be clarified. Italian Prime Minister Matteo Renzi called for a full investigation of the crash, declaring an “absolute need to understand who was responsible and shed clarity on the incident.”

“We will not rest until we clarify what happened,” he said.

All rail traffic around the area is currently blocked.

The deadliest train incident in Italian history was not a crash but a mass poisoning in 1944 that killed the train’s crew and almost all the passengers, including several hundred stowaways. The steam-hauled service stalled in a mountain tunnel and was unable to get underway again, with the fire burning in the engine’s boilers creating carbon monoxide gases that killed over 500. The only survivors were the passengers in the last few carriages that remained in the open air when the train stopped.

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