Ukraine steelworks troops surrender

Russia said Thursday that 1,730 Ukrainian soldiers had surrendered this week at Mariupol's Azovstal steel plant, after a desperate battle that has become emblematic of the nearly three-month-old war.

The number included 80 wounded who were taken to a hospital in Russia-controlled territory in eastern Ukraine, Moscow said.

The Russian defence ministry released a video appearing to show exhausted Ukrainian soldiers trudging out of the sprawling steelworks, after a weeks-long siege forced the defenders and civilians to huddle in tunnels, enduring dire shortages of food, water and medicine.

Russian troops patted down those surrendering and inspected their bags as they left, signalling the effective end of what Ukraine's government had called a "heroic" resistance.

The International Committee of the Red Cross said it had registered "hundreds of Ukrainian prisoners of war" from the plant in Mariupol, a port city obliterated by Russian shelling.

Ukraine is hoping to exchange the Azovstal soldiers for Russian prisoners. But pro-Kremlin authorities in Ukraine's eastern Donetsk region said some of them could be put on trial.

The United States warned Thursday it would be watching the situation closely.

"Our expectation is... that all prisoners of war will be treated in accordance with the Geneva Convention and the law of war," Pentagon spokesman John Kirby said.

Ukraine has already begun its own process of trying captured troops for crimes they are alleged to have committed, with prosecutors detailing 12,595 counts -- including the horrific bombing of a maternity ward in Mariupol.