Four people died and 75 more were injured when a gunman threw grenades and opened fire from a rifle at a busy central square in the Belgian city of Liege on Tuesday, before shooting himself, Reuters reports. It was not immediately clear what the attacker’s motive was, and he appears to have no history of terrorist attacks, according to prosecutors. However, justice officials told Reuters that the man was due to appear before police on Tuesday and had previous convictions for illegal possession of arms and drugs.