Hundreds of bodies have been discovered buried under the rubble of an apartment building in Mariupol painting the devastating aftermath of Russia's siege on the Ukrainian city.

Workers who were digging through the ruins of the building found 200 bodies in the basement, said Ukrainian authorities on Tuesday. The discovery is the latest horror that has come to light in the ruined city that has seen some of the worst sufferings of the three-month-old war between the two European nations.

Aftermath of Mariupol Siege

The uncovered bodies were already decomposing and the stench hung over the entire neighborhood, said Petro Andryushchenko, who is an adviser to the mayor of the city. The official did not reveal when the bodies were discovered but noted that the sheer number of victims makes it one of the deadliest known attacks of the war.

Meanwhile, heavy fighting was reported in the Donbas, the eastern industrial heartland that Moscow's forces are intent on seizing. Russian military forces took over an industrial town that hosts a thermal power station and continued to increase efforts to encircle and capture Sievierodonetsk and other Ukrainian cities, as per the Associated Press.

It was reported that 12 people were killed by Russian shelling in the Donetsk region of the Donbas, said the regional governor. The governor of the Luhansk region of the Donbas said that the area was facing its "most difficult time" in the eight years since separatist fighting began.

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In a Telegram post, Gov. Serhii Haidai said that the Russian troops were advancing in all directions at the same time. The official noted that the military forces brought over an "insane number of fighters and equipment." He said the invaders were killing their cities and destroying everything around them.

According to USA Today, the city of Mariupol has been left devastated by weeks of continued missile attacks by Russian forces. Last week, the last of the remaining Ukrainian fighters in the region surrendered, giving Moscow complete control of the city that housed 450,000 people before the war. An estimated 100,000 residents remained in the city as Mayor Vadym Boychenko claims that the Russian bombardment of the city has killed thousands of civilians.

Russia's War on Ukraine

Ukrainian President Volodymyr Zelensky earlier accused Russia of attempting to inflict as much death and destruction as possible on his country. In his nightly address, he said, "There has not been such a war on the European continent for 77 years."

The siege was estimated to have killed roughly 21,000 people, said Ukrainian authorities, who said that Russia was trying to cover up the horrors by bringing in mobile cremation equipment and burying the dead in mass grave sites.

The situation comes as Moscow-backed separatists have been fighting Ukrainian forces in the Donbas for the last eight years and are in control of large swaths of territory. Haidai noted that the Russian military was focusing its efforts on carrying out an offensive in order to encircle the two Donbas regions. He added that the intensity of fire has increased by multiple times, Aljazeera reported.

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