The Russian president has rejected requests from commanders in the field that they be allowed to retreat from Kherson, a vital city in Ukraine’s south.
Ukraine’s president did not mention the accident during his nightly address.
The United States has proposed exchanging Brittney Griner and another American jailed in Russia for Mr. Bout, who was convicted in 2011 on charges including conspiring to kill American citizens.
Russian attacks on civilians have underscored the need to hold war crimes to account. But the prosecutor of the International Criminal Court warned against a “stampede” of investigations.