Armenia and Azerbaijan announced an agreement early on Tuesday to halt fighting over the Nagorno-Karabakh region of Azerbaijan under a pact signed with Russia that calls for deployment of nearly 2,000 Russian peacekeepers and territorial concessions. Nagorno-Karabakh has been under the control of ethnic Armenian forces backed by Armenia since a 1994 truce ended a separatist war in which an estimated 30,000 people died. Since then, sporadic clashes erupted, and full-scale fighting began on September 27. Several ceasefires had been called but were almost immediately violated. However, the agreement announced early on Tuesday appeared more likely to take hold because Azerbaijan has made significant advances, including taking control of the strategically key city of Shushi on Sunday. Armenian Prime Minister Nikol Pashinyan said on Facebook that calling an end to the fight was "extremely painful for me personally and for our people."