The city has become ‘the heart’ of the war, a Ukrainian official says

A new international effort raced to rescue more civilians from the tunnels under a besieged steel plant in Mariupol and the Ukrainian city at large, even as fighters holed up at the sprawling complex made their last stand to prevent Moscow’s complete takeover of the strategic port.

A convoy of buses left Mariupol on Wednesday in a new attempt by Ukraine, the U.N. and the International Committee of the Red Cross to evacuate civilians from the southern Ukrainian city, the regional governor said.