According to police in Liège, the explosion occurred on the street in front of the synagogue. The blast caused material damage to the synagogue and blew out windows on buildings on the other side of the street. The area has been cordoned off, RTBF reports.
The federal police's terrorism unit has been called in on the case, according to the same source. The city's mayor says it is a clear anti-Semitic crime that has been committed. Police are investigating what caused the explosion in an initial stage.
The exact time the explosion occurred during the night to Monday has not been released. It is unknown whether there were any injuries or fatalities from the explosion.