Deputy mayor of Mariupol Serhiy Orlov confirmed the release of chemicals from a Russian drone in the city.

"We cannot provide more detailed information, but we have confirmation from the military that this happened," Orlov said in a BBC comment.

As reported, on the evening of April 11, the Azov Regiment said that Russian occupying troops dropped a poisonous substance of unknown origin from an unmanned aerial vehicle on Ukrainian military and civilians in Mariupol. The victims have respiratory failure, vestibulo-atactic syndrome. The consequences of using an unknown substance are being clarified.

Azov leader Andriy Biletsky reported three victims. "A few hours ago, the Russians hit Mariupol with chemical weapons, Azovstal plant – the fortress of Ukrainian fighters, Azov soldiers. If we talk about the practical side of the blow, it is small. Three people have clear signs of chemical poisoning, but without catastrophic consequences," he said in a video statement on Tuesday night.

Later, British Foreign Secretary Liz Truss said the country was working with partners to verify details about a possible use of chemical weapons in Mariupol.

Deputy Head of the Ministry of Defense of Ukraine Anna Maliar also said that information about the possible use of chemical weapons by the invaders in Mariupol is being checked by the Ukrainian authorities.