Counter-terrorism police were reportedly dispatched to the scene and were able to arrest two people.
Police and emergency workers stand outside the main railway station following what police described as an axe attack on March 9 in Dusseldorf, Germany.
One photo from the scene shows paramedics treating someone lying on the ground, taped off by a cordon.
He killed 12 people, including the lorry's registered Polish driver, and was shot dead four days later in Italy after firing first at police there.
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"I helped her wound and called her father", she said. The train station remains closed and trains have been diverted.
Earlier, a spokesman for federal police, who are usually in charge of policing train stations, had said two people were arrested and further attackers might be on the run.
Heavily-armed special police forces swooped in on the station, located in the center of Germany's ninth-largest city.