Russia is bogged down in an increasingly costly, uncertain and grinding military campaign, with untold numbers of dead, no immediate end in sight, and encircled by western sanctions biting hard on its economy and currency.

Explosions and bursts of gunfire shook Kyiv, and heavy artillery fire could be heard from the northwest, where Russia has sought to encircle and capture several of the capital’s suburban areas.

Perched on the Sea of Azov, Mariupol has been a key target that has been relentlessly pounded by Russian assaults for more than 3 weeks and has seen some of the worst suffering of the war.