good evening and welcome to the bbc news at six. i m live in kyiv where the russian advance on the capital creeps ever closer to the centre of the city. overnight, the russians attacked a nuclear plant, europe s biggest, in zaporizhzhia. the fires and shelling sparked fears of a nuclear leak, which led to ukrain s president zelensky again calling for a no fly zone over the country. if we take a look at the map, the areas in red show the gains russia is making in the country. they control large areas of the south and are targetting the city of mariupol which if captured would cut off ukraine s access to the black sea. another key target is kharkiv in the east, ukraine s second largest city. our eastern europe correspondent, sarah rainsford, has this special report from inside kharkhiv, which has been bombarded by russian forces this week.