The incident happened at 6.30am on a regional OeBB train heading towards Bregenz in the western Austrian state when the 60-year-old man stabbed the two passengers with a knife.
According to the police, two victims suffered considerable injuries and were taken to hospital. Reports in vol.at suggest one of the victims was a 19-year-old sitting opposite the suspect who was stabbed in the stomach. The German is then thought to have attacked a 17-year-old, injuring them in the throat.
A 22-year-old passenger who helped the police detain the suspect also received an injury to his hand.
The investigation is ongoing.
The attack came days after a 27-year-old Swiss national went on a knife rampage on a train in Switzerland, killing one passenger and injuring five. Austrian police have ruled out any link between the Swiss attack and today's incident.