America's Warning to Russia: Back Off Syria By Heather Sells CBN News Reporter Thursday, September 10, 2015 The U.S. is growing increasingly worried over signs of increased Russian military presence in Syria and has warned Moscow to back off. On Wednesday, Secretary of State John Kerry spoke to Russian Foreign Minister Sergey Lavrov for the second time in five days. U.S. State Department spokesman John Kirby said that Kerry "reiterated our concern about these reports of Russian military buildup." Kirby added that if the reports are true it could "lead to greater violence and even more instability." Also on Wednesday,...