Ukraine’s military and security services carried out a deadly attack on a key bridge that connects the Crimean Peninsula to the Russian region of Krasnodar, a Ukrainian official said Monday. Ukraine used sea-surface drones to attack the bridge — a supply artery for Russia’s war in Ukraine — the official said, speaking on the condition of anonymity because of the sensitivity of military operations. On Monday, Russia said it would resume its military blockade on Ukrainian grain, suspending a United Nations-backed deal that allowed shipments from Black Sea ports despite wartime hostilities.