On April 2, the parties to the Karabakh conflict accused each other of violating truce along the front line. The claims came from defense authorities of Armenia and of Azerbaijan. Neighboring Armenia and Azerbaijan fell out with each other in the late 1980s because of Nagorno-Karabakh, the disputed territory that had been part of Azerbaijan before the Soviet Union break-up but was mainly populated by Armenians. In 1991-1994, the confrontation spilled over into large-scale military action for control over the enclave and some adjacent territories. Thousands left their homes on both sides in a conflict that killed 30,000. A truce was called between Armenia and the Nagorno-Karabakh republic on one side and Azerbaijan on the other in May 1994.