An eight-year-old boy died and his mother was injured when a man pushed them in front of a high speed train at Frankfurt train station in Germany. A 40-year-old man has been arrested over the attack on Monday morning. Witnesses said the man deliberately pushed the boy and his mother on to the tracks before trying to run from the scene. He was chased and restrained by passers-by before being arrested. Local media reported that the suspect was an Eritrean citizen. "The boy and his mother were pushed in front of an arriving train. The mother was able to save herself," a police spokeswoman said. Police confirmed they had launched a murder inquiry. Investigators said they do not believe the suspect knew the victims and they are not yet aware of any motive. The mother was taken to hospital for treatment but the extent of her injuries was not immediately clear. The attack came 10 days after a 34-year-old woman was fatally pushed in front of a train by a man in the German town of Voerde. Boy dies after being pushed in front of train This is just sick! That poor boy! And I can't even imagine the horror the mother must have felt being unable to help her son. Brave people who tackled and held the guy down. He could have had a knife too. Very brave.