Casualties of Russia's war in Ukraine emerged in stark relief as a new satellite image showed an expansion of a cemetery in the vital port city of Mariupol, which Russian forces now control – except the iconic Azovstal Iron and Steel Works.

A satellite photo from Maxar Technologies revealed the expansion of the Starokrymske Cemetery on Thursday, May 12, 2022.

Maxar Technologies satellite photo of the Starokrymske Cemetery in Mariupol, Ukraine

Maxar Technologies satellite photo of the Starokrymske Cemetery in Mariupol, Ukraine (Satellite image ©2022 Maxar Technologies)

"Russian digging of mass graves continues in Mariupol in an attempt to cover up war crimes at Starokrymske Cemetery on the west edge of the city," Foreign Policy Magazine's Jack Detsch noted on Twitter.

The United Nations Human Rights High Commissioner claimed Thursday that Russian forces have killed thousands of Ukrainian civilians in Mariupol since the war began, although the "true scale" of atrocities has yet to be revealed.

UN SAYS RUSSIAN FORCES IN MARIUPOL HAVE KILLED ‘THOUSANDS’ OF CIVILIANS, INVESTIGATIONS REMAIN ONGOING

"We estimate the civilian death toll in Mariupol to lie in the thousands, while only with time will the true scale of atrocities, casualties and damage become clear," High Commissioner Michelle Bachelet said. "I am shocked at the scale of the destruction, and the numerous violations of international human rights law and international humanitarian law that have reportedly been committed in the city."

Mariupol’s mayor alleged in mid-April that an estimated 21,000 civilians had been killed in the port city amid Russia’s invasion.  But the UN has not been able to validate these figures. 

Smoke rises above Azovstal steelworks, in Mariupol, Ukraine, in this still image obtained from a recent drone video posted on social media. 

Smoke rises above Azovstal steelworks, in Mariupol, Ukraine, in this still image obtained from a recent drone video posted on social media.  (MARIUPOL CITY COUNCIL/via REUTERS )

On Thursday the UN reported that there has been at 7,326 civilian casualties with 3,541 killed and 3,785 injured across Ukraine. 

But the top intergovernmental body has repeatedly warned these figures are likely significantly higher. 

Bachelet said the "vast majority" of civilian causalities have been caused by Russia’s insistent use of explosive weapons like heavy artillery, multiple launch rocket systems, missiles and air strikes.

UKRAINIAN FIGHTER IN MARIUPOL STEEL PLANT ASKS ELON MUSK FOR HELP

Russian forces have taken the entirety of Mariupol, except the Azovstal plant, where approximately 1,000 Ukrainian fighters remain defiant, holed up in the tunnels beneath the plant.

In this handout photo taken from video released on Wednesday, May 4, 2022, by Donetsk People's Republic Interior Ministry Press Service, Smoke rises from the Metallurgical Combine Azovstal in Mariupol, in territory under the government of the Donetsk People's Republic, eastern Ukraine.

In this handout photo taken from video released on Wednesday, May 4, 2022, by Donetsk People's Republic Interior Ministry Press Service, Smoke rises from the Metallurgical Combine Azovstal in Mariupol, in territory under the government of the Donetsk People's Republic, eastern Ukraine. (Donetsk People's Republic Interior Ministry Press Service via AP)

Ukrainian and Russian officials had said the last remaining women, children and the elderly were evacuated from the plant earlier in the week, but confusion remained whether all civilians had been evacuated after two Ukrainian officials estimated Tuesday that some remained.

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U.S. President Biden, Ukrainian President Volodymyr Zelenskyy, and others have accused Russia of committing war crimes after Ukrainians and other visitors discovered dead bodies in mass graves in Bucha, a city on the outskirts of Kyiv, following the Russian withdrawal from Ukraine's capital city.

Fox News' Caitlin McFall contributed to this report.