Kenya is cracking down on the daily flights that deliver "Khat" (a leaf that is chewed by Somalis to provide a buzz similar to a lot of caffeine). The leaf must be chewed fresh, does not grow in Somalia, thus the daily flights. But illegal Somali passengers fly back on the returning Khat flights, and now these passengers must have valid visas. Khat is Somalia's major import, and a major export from Kenya.