A Ukrainian sapper searches for unexploded explosives at the Antonov An-225, world's biggest cargo aircraft during recent fighting between Russian and Ukrainian forces, at the Antonov airport in Hostomel, on the outskirts of Kyiv, Ukraine, Thursday, May 5, 2022. (AP Photo/Efrem Lukatsky)
Municipal workers attach a Russian national flag to a pole preparing to celebrate 77 years of the victory in WWII in Mariupol, in territory under the government of the Donetsk People's Republic, eastern Ukraine, Thursday, May 5, 2022. Heavy fighting is raging at the besieged steel plant in Mariupol as Russian forces attempt to finish off the city's last-ditch defenders and complete the capture of the strategically vital port. (AP Photo)
Injured Natalia Rudneva, 59, reacts as her son was hospitalised after night shelling in Kramatorsk, Ukraine, on Thursday. (AP Photo/Andriy Andriyenko)
A view of an apartment building destroyed by night shelling in Kramatorsk, Ukraine, Thursday, May 5, 2022. (AP Photo/Andriy Andriyenko)
LVIV, Ukraine — Ukrainian fighters in the tunnels underneath Mariupol’s pulverized steel plant held out against Russian troops Thursday in an increasingly desperate and perhaps doomed effort to deny Moscow what would be its biggest success of the war yet: the complete capture of the strategic port city.