STORY: Apartment buildings with blackened walls and piles of rubble – this is what remains of much of the Ukrainian port city of Mariupol.Two months of bombardment and siege by Russian forces have reduced the once thriving city to a wasteland.It has seen the bloodiest fighting and worst humanitarian catastrophe of the war.Ukraine says 100,000 civilians remain there.Among them is social worker Oxana Hvostenko.She says there is literally nothing left of her home – all that remains is a toilet, a door and a hallway.After losing her home, Hvostenko is staying with her friend Sergei Gradovich.”Who should I thank for this? Tell me. Was it necessary to bomb civilians with such bombs. You have to be a fanatic to do it. No shame, no conscience, no feeling of proportion. Nothing. They made the whole block homeless in old age.” After failing to capture Kyiv in a nine-week assault that has turned cities to rubble, killed thousands and forced 5 million Ukrainians to flee abroad, Russia is now focusing on the east and south of Ukraine.Ukraine’s armed forces said on Saturday that Russia had failed to capture three target areas.Moscow said on Saturday its artillery units had struck 389 Ukrainian targets overnight.Britain’s defence ministry said on Saturday that Russia had been forced to merge and redeploy depleted units from failed advances in northeastern Ukraine.Reuters could not independently verify the reports on what was happening on the ground.Ukraine’s border guard service posted a video on its Facebook page showing about 16 weary-looking soldiers in battle fatigues, singing the national anthem in a small basement room.The service said the fighters were border guards helping to defend Mariupol’s Azovstal steel works, the last bastion of Ukrainian forces holding out against Russian invaders.Reuters could not verify the video.Russia denies targeting civilians in what it says is a “special military operation” to disarm and “denazify” its southern neighbor.Ukraine and its western allies call that a baseless pretext for a war of aggression.