The United Nations Security Council has held an emergency meeting on the deepening crisis in Ukraine, as the West condemns Russia for its role in the growing conflict.
The Council on Thursday expressed deep concerns about the escalation of violence in eastern Ukraine and called for an immediate ceasefire.
NATO estimates 1-thousand Russian troops are fighting alongside the separatists, a development that's also been confirmed by U.S. and British officials.
U.S. Ambassador Samantha Power also accused Russia of "manipulating and outright lying" about their involvement.
Moscow's diplomat shot back and suggested Washington stop interfering in the affairs of sovereign nations.
Earlier, Ukraine's Defense and Security council said Russian tanks and military vehicles had rolled in and taken a border town as well as other parts of the country's southeast.