Frustration and anger among the refugees and illegal immigrants in Greece is growing, causing concerns for Greek authorities, especially after the Brussels terrorist attacks. In separate incidents some 150 blocked the highway Thessaloniki-Kilkis in northern Greece in a protest against the closed borders between Greece and FYROM. This resulted in a minor traffic jam. The refugees later dispersed and returned to their lodges near the Evzones customs check point. In another case a protest is under way at the bridge of Polykastro in Kilkis, where some refugees are also voicing their objection to the closing of the Greek-FYROM borders. Meanwhile, refugees and illegal immigrants staged a sitting protest earlier at the port of Thessaloniki also making the same demands.