AlQa'dah 09, 1436, August 24, 2015, SPA -- The United Nations' refugee agency has called on Europe to band together in dealing with the ongoing migrant crisis following chaotic scenes at the weekend in Greece, Macedonia and Serbia, dpa reported. More capacity is required to ensure the safety of migrants on their journey to other parts of Europe, according to a statement Sunday night from the United Nations High Commissioner for Refugees (UNHCR). An estimated 7,000 migrants arrived in Serbia in the night to Sunday after neighbouring Macedonia caved into pressure and opened its borders following clashes with police on Friday. UNHCR plans to build more reception centres for refugees at the border region, according to the statement. The organization also criticized Athens for failing to register migrants before entering Macedonia. Other European Union member states must also step up to help, according to UNHCR Europe Bureau Director Vincent Cochotel, who said the problem "will not go away any time soon and affects all of Europe."