The collision happened at a railway crossing with a half-barrier in the area of Lohma near Gera, according to federal police. When the freight train crossed over that section of the tracks, it caught the van sideways and dragged the vehicle along for about 200 metres. How this happened exactly remains unclear.
The three passengers inside the van who were killed have been identified as a 49-year-old woman, a 17-year-old girl and a 19-year-old man, police said.
According to statements by the train driver and observations by witnesses, the barrier was closed at the time of the collision.
The train driver was also found to have had a blood alcohol level of 0.0.
A rescue helicopter was flown to the scene, but it was already too late to save the van's passengers.
After the collision, the train line was closed off and a replacement bus service was deployed.