Relentless attacks pound last defenders holed up in Mariupol

A damaged boat of the Ukrainian coastguard of the Sea of Azov is seen after heavy fighting in an area controlled by Russian-backed separatist forces in Mariupol, Ukraine (Alexei Alexandrov/AP)

Relentless Russian attacks pounded the last Ukrainian stronghold in the besieged city of Mariupol as a fighter apparently on the inside issued a video plea for help, saying defenders holed up in a giant steel factory “may have only a few days or hours left”.

Another attempt to evacuate civilians trapped in the pulverised port city failed on Wednesday because of continued fighting, and the number of people fleeing Ukraine passed five million.