Experts explain how Ukraine launched its own invasion of Russia

Ukraine launched the biggest invasion of Russia since World War Two when it breached Russia's Kursk region. Russia appears to have been taken by surprise.

Later that morning, as Ukraine began the biggest invasion of Russia since World War Two, the ministry published video showing General Valery Gerasimov, commander of the Russian war effort, visiting a different combat zone, also in Ukraine. He heard reports from commanders and set "tasks for further actions," it said.