A Saudi Arabian doctor was reportedly arrested after allegedly driving a car into a crowd at a Christmas market in Germany.

Authorities have not formally named the suspect in the car ramming in the city of Magdeburg that killed at least five people and wounded hundreds, saying only that he is a Saudi doctor who has lived in Germany for nearly two decades and that he acted alone.

Shamsud-Din Jabbar, the driver behind the Bourbon Street attack on New Year’s, researched New Orleans and the deadly Christmas market attack in Germany in the hours and weeks before the attack, the FBI said in an update Tuesday.