Rebel Russian mercenaries barrel towards Moscow

(Reuters) - Mutinous Russian mercenary fighters barreled towards Moscow on Saturday after seizing a southern city overnight, with Russia's military firing on them from the air but seemingly incapable of slowing their lightning advance. Facing the first serious challenge to his grip on power in his 23-year rule, President Vladimir Putin vowed to crush an armed mutiny he compared to Russia's Civil War a century ago. The fighters of the Wagner private army run by former Putin ally Yevgeny Prigozhin were already most of the way to the capital, having captured the city of Rostov and set off on a 1,100 km (680 mile) race to Moscow. Reuters saw troop carriers and a flatbed truck carrying a tank careening past the city of Voronezh more than halfway to Moscow, where a helicopter fired on them. But there were no reports of the rebels meeting any substantial resistance on the highway. Russian media showed pictures of small groups of police manning machine gun positions on Moscow's southern outskirts. Authorities in the Lipetsk region, south of the capital, told residents to stay home.