Leaked US intelligence documents reveal that more than twice as many Russian soldiers as Ukrainian soldiers have been killed while fighting in Ukraine. "The Department of Defense continues to review and assess the validity of the photographed documents that are circulating on social media sites and that appear to contain sensitive and highly classified material," Deputy Pentagon Press Secretary Sabrina Singh said in a statement shared with Insider in response to queries about the Russian and Ukrainian casualties. We have referred this matter to the Department of Justice, which has opened a criminal investigation," Singh added