Prosecutors expect to charge the suspected driver in a car-ramming at a Christmas market in Germany with murder and attempted murder, the head of the local prosecutor's office said on Saturday.

The motive for the attack remains unclear but the suspect's dissatisfaction with Germany's treatment of Saudi refugees may have played a role, the prosecutor in the central city of Magdeburg told a press conference following Friday's attack, in which five people were killed and more than 200 were injured.