Pentagon monitoring reports of possible Russian chemical weapons attack in Mariupol

If Russia were to have used chemical weapons, it would signal a major escalation of its botched invasion of Ukraine, which has stalled after more than a month.

Pentagon monitoring reports of possible Russian chemical weapons attack in Mariupol

Armoured vehicles of pro-Russian troops drive along a street during Ukraine-Russia conflict in the besieged southern port city of Mariupol, Ukraine March 31, 2022. 

Alexander Ermochenko | Reuters

WASHINGTON — Defense Department press secretary John Kirby said the Pentagon was closely monitoring reports Monday evening of a possible Russian chemical weapons attack on the besieged Ukrainian city of Mariupol.

If Russia were found to have used chemical weapons in the strategic holdout city, it would represent a major escalation of the conflict and present a direct challenge to NATO to act.

"We are aware of social media reports which claim Russian forces deployed a potential chemical munition in Mariupol, Ukraine," Kirby said Monday. "We cannot confirm at this time and will continue to monitor the situation closely."

"These reports, if true, are deeply concerning and reflective of concerns that we have had about Russia's potential to use a variety of riot control agents, including tear gas mixed with chemical agents, in Ukraine," said Kirby.

British Foreign Secretary Liz Truss also said her government was working "urgently" to verify details an alleged attack.

The original report was in the form of a Telegram message posted by the Azov Regiment, an ultra-nationalist part of the Ukrainian National Guard. The Azov message said Russian forces used "a poisonous substance of unknown origin." 

"Any use of such weapons would be a callous escalation in this conflict, and we will hold Putin and his regime to account." Truss wrote on Twitter.

U.S. officials have been warning for several days that the Russian army will almost certainly continue to commit what they call "atrocities" as it doubles down on attacks in the eastern regions of Ukraine.

"Russian leaders have shown in the past ... the brutality with which they conduct and prosecute their operations," Kirby told reporters earlier in the day Monday, citing Russia's alleged use of chemical weapons during the Syrian civil war as an example.

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