Kiev’s 2.8 million inhabitants have been told to head to air raid shelters if possible, amid a Russian invasion of Ukraine. Air raid sirens sounded across the capital during Thursday as a trial. Martial law has been in force throughout the country since 5:30 am (0230 GMT) by decree of President Volodymyr Zelensky, for an initial period of 30 days. Russian President Vladimir ordered the invasion of the separatist regions of Luhansk and Donetsk in eastern Ukraine overnight to Thursday. However, there has already been fighting near Kiev, for example at a military airfield.