United Nations Secretary-General Ban Ki-moon is in Burundi to encourage dialogue between the government and its opponents amid violent unrest.

Ban was welcomed at the Bujumbura airport Monday by Vice President Gaston Sindimwo and hundreds of people lined the streets to get a glimpse of the U.N. chief. Ban will meet with some Burundian politicians and leaders of civic groups.

Gun and grenade attacks continue to plague Burundi, especially the capital, Bujumbura, as President Pierre Nkurunziza's supporters and opponents target each other.

Deputy police spokesman Moise Nkurunziza said three people were killed in gun and grenade attacks Sunday in Bujumbura and another was killed in a blast on Monday.

Burundi's violence stems from Nkurunziza's decision last April to seek a third term which he won.