The International Committee of the Red Cross said on Sunday that it was “deeply alarmed” by the situation in Mariupol, calling for unimpeded access to help residents, including hundreds of wounded.

Russian forces continued on Sunday to drop heavy bombs from the air and direct artillery fire at the sprawling Azovstal steel factory, where a few thousand Ukrainian soldiers and civilians are holed up, according Mykhailo Podolyak, an adviser to the Ukrainian President.

There were signs, he said, that Russian troops were gathering around the plant for a possible assault.

The Red Cross has tried repeatedly in recent weeks to send a humanitarian convoy to Mariupol to help treat injured people and evacuate the remaining civilians, but violence has stymied the efforts. Tens of thousands of civilians are believed still to be in the city, out of a pre-war population of nearly half a million.

“Immediate and unimpeded humanitarian access is urgently required to allow for the voluntary safe passage of thousands of civilians and hundreds of wounded out of the city, including from the Azovstal plant area,” the group said.

New York Times News Service