A man fatally stabbed two people and injured five others on a train in northern Germany on Wednesday before being arrested, police said.

Germany's Federal Police force said the man used a knife to attack several passengers shortly before a regional train traveling from Kiel to Hamburg arrived at the Brokstedt station.

Police spokesman Juergen Henningsen from the nearby city of Flensburg said two of the stabbed people died after the attack. Three people were severely injured and two others suffered minor injuries. No details were given about the identity of the victims.

The attacker was also injured and taken to the hospital, police said.

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Police did not provide any information on the suspect’s identity and said his possible motives were under investigation. They said they were first alerted to the incident shortly before 3 p.m. when several passengers on the train made emergency calls to police.

The interior minister of Schleswig-Holstein state, Sabine Suetterlin-Waack, voiced shock at the attack..

“It is terrible,” Suetterlin-Waack told German public broadcaster NDR. “We are shocked and horrified that something like this has happened.”

Regional police and the federal police were on the scene and the prosecutor’s office was investigating the attack, NDR reported.

The train station in Brokstedt was closed for several hours and train traffic was delayed across northern Germany.

Train operator Deutsche Bahn expressed its condolences on Wednesday evening saying that “our deepest sympathy goes to the relatives of the victims. We wish those injured a speedy and complete recovery.”