The UN refugee agency says that a record 800,000 people were forced to flee across borders last year. Many of them were displaced by conflicts in their home countries. Mali is one example. More than 320,000 people have been forced from their homes since January because of fighting between government forces and Tuareg rebels.Many are seeking refuge in neighbouring countries - which are struggling to cope with the influx. The situation is particularly precarious as the Sahel region is going through a major drought.