Russian forces on Monday used tanks and artillery in "storming operations" at the Azovstal steel plant in Mariupol where the city's last defenders are holed up, Ukraine's defence ministry said.
Russia has declared victory in Mariupol, a strategic city on the Sea of Azov, but the sprawling steel works remains in the hands of Ukrainian fighters.
Defence Ministry spokesman Oleksandr Motuzyanyk gave few details and it was not clear whether Russian forces had launched a new operation at Azovstal. Reuters could not verify the situation at the plant.
"The enemy continues to blockade our units in the area of the Azovstal factory, and is conducting storming operations with the support of tank and artillery fire," he told an online briefing.
Raising the prospect of Russia stepping up its assault on the steel works further, he said: "The possibility of a renewal of its bombardment from Tu-22 M3 bombers is not excluded."
Russia has previously denied assertions by Ukrainian officials that it has tried to storm the steel works.
Russian President Vladimir Putin said on April 21 that it was not necessary to storm the steel works but called for Russian forces to blockade the area "so not even a fly can get through". Ukrainian officials said days later that Russia had started an assault on Azovstal.
Ukraine has said all women, children and elderly civilians that were also in Azovstal have now left. Russia has said the evacuation of civilians from the plant is complete.
(Reporting by Max Hunder, Editing by Timothy Heritage)
