Nancy, France ? A fire on an overnight train in eastern France filled a sleeping car with deadly smoke Wednesday, killing 12 people including five Americans from the same family and driving panicked passengers to smash windows and jump to safety.

The train, like others in Europe, had no smoke detectors even though cigarette smoking is allowed in designated cars.

Fatal rail accidents are rare in France, where trains are known for speed, safety and efficiency. Accidents, however, are not unknown in Europe: A high-speed train derailed in Germany in 1998, killing 101 people.

Wednesday’s blaze, which also injured nine people, was initially blamed on an electrical short-circuit. But the French rail authority SNCF said that was premature and the cause was under investigation.

The owner of the sleeping car, German national railroad Deutsche Bahn, said the fire apparently started in the compartment of a train attendant. Smoke was blamed for the deaths.

The fire began shortly after 2 a.m. as the train with 150 passengers passed through the city of Nancy on its way to Munich, Germany, according to SNCF. The train had left Paris three hours earlier.

An accountant from North Branford, Conn. and four members of his family were killed. Salvatore Michael Amore, 43, and his family were traveling to Paris from Germany when they were killed, said Anna Maria Amore, his sister-in-law. Also killed were Amore’s wife, Jeanne, 43; daughter Emily Jeanne, 12; son Michael Bernhardt, 8; and mother, Susanne, 72.

Also killed were three German men; a Russian man and woman; a Hungarian man and a Greek woman.

Firefighters inspect the coaches of the Paris-Vienna overnight express train that caught fire near Nancy, eastern France. Twelve passengers, including five Americans, were killed in the Wednesday blaze.

Authorities in Meurthe-et-Moselle prefecture said one American was among the nine people injured. All but one was treated at a hospital and released.

A train worker alerted authorities at about 2:15 a.m. when he spotted smoke pouring from a car as the train passed the Nancy station.

Flames shot 9 feet into the air, and thick black smoke billowed out of the car’s windows.

Survivors told of panic inside the train as screaming passengers escaped by breaking through the car’s windows and climbing out once the train had stopped.

French survivor Marc Giraud said smoke filled his compartment after the door was opened. He grabbed an emergency ladder, smashed the window of the compartment and those inside crawled out.

“We got out through that mouse hole,” Giraud told TF1 television. “I don’t know how we got out through there.”

Firefighters rushed to the train, which stopped on a track about 800 yards outside the Nancy station.

All the dead were inside the charred sleeping car, said regional official Jean-Francois Cordet.