The incident happened as the train arrived at Ottignies. The unidentified person was not a member of the train's crew, but did manage to gain access to the intercom.
He went on to announce: "Ladies and Gentlemen, we are travelling to Auschwitz. All Jews are requested to alight in order to take a shower."
Several press outlets in southern Belgium have labelled the incident a 'misplaced joke'.
Following an internal enquiry the rail company decided to file a complaint with the Belgian judicial authorities. The company has vigorously condemned the words spoken and this is a message it has also passed on to Jewish organisations in Belgium. Belgian rail stresses that abuse of a train's PA system that forms part of the safety system on board trains is a crime that can lead to a fine or a custodial sentence.