Russia-Ukraine war latest: 1m refugees have fled since invasion; Russian controls imposed in Kherson, says mayor– live

We have witnessed an exodus,' says UN; people in crucial Black Sea port of Kherson told to follow Russian measures; 38 countries refer reports of atrocities to ICC, the largest referral in court's history

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• Russia-Ukraine war: what we know on day seven
• Ukraine faces humanitarian crisis amid Russian missile attacks
• Biden vows to make Putin pay' for invasion
• It might be the last chance': citizens flee Kyiv as assault intensifies
• What more could the west do about Russia's invasion of Ukraine?

Researchers are gathering evidence of possible Russian war crimes in Ukraine.

My colleague, Dan Sabbagh, reports that an open-source intelligence community' is already collecting and studying video and photo evidence that Russia's military is committing war crimes with deadly attacks on civilians and the use of cluster munitions.