Residents of Ukraine's capital who were unable or unwilling to flee the city under siege take refuge underground from mortars and Grad missiles

Ukrainian leader urges Russian citizens to pressure leader Putin to stop invasion, amid reports of fierce national resistance to attack

Workers will cross border to Ukraine daily to provide consular services; Foreign Ministry tells Israelis at border crossings to visibly bear 'IL' lettering for quick assistance

Mayor Vitali Klitschko says missile slams into high-rise building on southwestern outskirts; number of victims 'being specified,' evacuation underway, authorities say

Top advisor to Ukrainian president says military successfully holding off Russian assaults; apartment block in capital hit by Russian shelling

'The fight is here,' president tells US officials from secret whereabouts; street fighting against Russian forces underway in Kyiv, officials say

'This night will be more difficult than the day,' Ukraine president tells his people in a video adress after midnight, adding that several cities are under attack

'We're all here defending our independence, our country, and it will stay this way,' leader says in defiant video from bombed capital

Most moving to Poland and Moldova, and many more are heading for the borders, officials say

From attempts at negotiations and the danger posed to civilians, to punitive measures and the pope's personal appeal -- a look at the latest developments