announcer: this is nbc nightly news with lester holt. good evening, everyone russian intentions are still difficult to sort out, but judging by their actions, kyiv is still very much in their sites tonight. while putin s forces pivot to the east, u.s. military officials say the tempo of russian air assaults has picked up over the last 24 hours and that the capital is very much under threat from air strikes. elsewhere, ukrainian troops say they continue to draw blood against the invaders this video of a russian tank burning recorded in slaboda, a village near kharkiv, which the ukrainians claim has been liberated. and there s word that the chernobyl nuclear plant is no longer in russian hands. troops pulling out today but only after some may have been exposed to the site s decades old radioactive soil richard engel reports from the front lines in eastern ukraine