At first, the fighters inside the empty school building, about 20 burly, heavily armed Russian mercenaries in dark fatigues, seemed trapped, recalled some of the Libyan militiamen who were there. But as the Libyans pushed forward, snipers opened fire from inside with high-powered rifles. Within minutes, three Libyan militiamen were killed, all shot in the head. Hundreds of Russian mercenaries, many highly trained and well-armed, are fighting alongside renegade Libyan commander Khalifa Hifter as he seeks to oust the country’s United Nations-backed government, according to Libyan military commanders and fighters, as well as U.S. military and other Western officials. These foreigners fighting for Hifter’s self-described Libyan National Army are introducing new tactics and firepower on the battlefield, threatening to prolong […]