The Liege attacks which left three people dead are being considered "terrorist murders", and the investigation now centres on whether the attacker acted alone, a Belgian federal magistrate said.
The attacker, identified as Benjamin Herman, shouted "Allahu akbar," the Arabic phrase for "God is great", several times during spree before he was shot down by a group of police officers, magistrate Wenke Roggen said.
Ms Roggeen said the attack is being treated as terrorism given the way Herman acted, which she said resembled Islamic State calls to attack police with knives and steal their weapons.
Allied to this is the fact that he yelled "Allahu Akbar", and had been in contact with radicalised people.
The attacker killed two female police officers by stabbing them from behind, stealing their service weapons and shooting them. He also killed a passer-by in a car before being shot dead by police.