Germans on Saturday mourned the victims after a doctor drove into a Christmas market teeming with holiday shoppers, killing at least five people, including a small child, and wounding at least 200 others.
Authorities arrested a 50-year-old man at the site of the attack in Magdeburg on Friday evening and took him into custody for questioning.
He has lived in Germany since 2006, practicing medicine in Bernburg, about 40 kilometers south of Magdeburg, officials said.
The state governor, Reiner Haseloff, told reporters that the death toll rose to five from a previous figure of two and that more than 200 people in total were injured.
Chancellor Olaf Scholz said that nearly 40 of them "are so seriously injured that we must be very worried about them.”
Mourners lit candles and placed flowers outside a church near the market on the cold and gloomy day.
Scholz and Interior Minister Nancy Faeser traveled to Magdeburg.
The chancellor called on the nation to stand together against hate.
Faeser ordered flags lowered to half-staff at federal buildings across the country.
