Three people were seriously injured in a knife attack on a German high-speed train on Saturday, authorities said.
The stabbings occurred in the morning on an InterCity Express (ICE) train between the Bavarian cities of Regensburg and Nuremberg.
Police said the sole suspected perpetrator, a 27-year-old man, had been arrested and there was no further threat to the public.
The motive for the crime was still "completely unclear," a Bavarian police spokesperson said.
Security sources said the suspect last lived in Passau, a city on the Austria border, and that he had arrived in Germany from Syria.
The victims are three men aged 26, 39 and 60.
Shortly after 9 am (local time) an emergency call from the ICE 928 train was received, said the spokesman of the police headquarters of the Upper Palatinate region of the state of Bavaria.
At that point the train was about halfway between Regensburg and Nuremberg.
An emergency stop was made at the at the small station of Seubersdorf, where a large contingent of of police cleared the train.
The 200 to 300 passengers disembarked and were cared for by more than 100 Red Cross responders.
Police have not yet said if train passengers or police officers ultimately subdued the attacker.
Interior Minister Horst Seehofer expressed his horror and called for calm. "The cruel knife attack in the ICE train is terrible," Interior Ministry spokesman Steve Alter quoted him as saying on Twitter.
Seehofer said he hoped that the injured and those who had to witness the act would recover quickly and completely.
Seehofer, who is in office in a caretaker role until a new government is formed, thanked the police emergency services and the train crew "for their courageous efforts."
The conservative Bavarian politician said that the background to the cruel act was still unclear and had to be clarified. "Only then is an evaluation possible."