Russia says evidence links concert hall attackers to "Ukrainian nationalists"

Russia's Investigative Committee said on Thursday it had uncovered evidence that the gunmen who killed more than 140 people in an attack on a concert hall last week were linked to "Ukrainian nationalists". In a statement, it said the attackers had received significant amounts of cash and cryptocurrency from Ukraine.

Ukraine has emphatically denied it had anything to do with the attack, the deadliest in Russia for 20 years.