Images from the southern Russian city of Rostov-on-Don, where the Wagner mercenary group has taken control of key military sites, show armoured vehicles and Wagner soldiers lining the streets as residents walk around them or watch on in groups. In an earlier televised address, Russian President Vladimir Putin acknowledged a "difficult" situation was unfolding in the city as Wagner leader Yevgeny Prigozhin vowed to oust the Russian military's top brass. IMAGES