Year End Africa 2018 - YEAR IN REVIEW. - Three men head north towards Algeria after crossing the Assamaka border post in northern Niger on Sunday, June 3, 2018. The International Organization for Migration has estimated that for every migrant known to have died crossing the Mediterranean, as many as two are lost in the desert. (AP Photo/Jerome Delay)
Three men head north towards Algeria after crossing the Assamaka border post in northern Niger in June. AP

Algeria defends expulsions after UN fears for 'stranded' migrants