Nearly two hundred people, including two dozen schoolchildren, sought medical assistance for suspected hydrogen sulphide poisoning in Volokolamsk, a town just outside Moscow. The symptoms — nausea, nosebleeds, vomiting, and fainting — were consistent with a leak from a well-known local landfill site.

And when officials arrived for a walkabout near the scene, they were met with an angry reaction.

“What are you f****** silent about?” one man shouts at Yevgeny Gavrilov, head of Volokolamsk region, before lashing out at him. “I’ll shove your glasses up your a**e”

In another scene, a little girl points an angry finger at the Moscow regional governor Andrei Vorobyov, before imitating cutting his throat . As he makes his way from the local hospital, locals shout “shame,” “killers” and throw snowballs in his direction.

Volokolamsk residents have long protested against the Yadrovo landfill, which, they say regularly floods the town with the stench of chlorine and hydrogen sulphide. On 3 March, as many as 5,000 attended a demonstration against the site. Their latest demonstration, on 8 March, had to be dispersed by police.

Authorities linked the latest leak to “low atmospheric pressure.” Speaking to local media, deputy governor Alexander Chuprakov said the cause of the emissions had been established “immediately.” Initially, however, state television had reported that children had been hospitalised following a strange “gas attack” at the local school.

Mr Chuprakov said he could not exclude the possibility of further uncontrolled emissions from the 40-year-old site.

Problems with the Yadrovo site have been well reported, and presidential candidate Ksenia Sobchak even made it part of her campaign. Ms Sobchak she had received a promise that the site would be closed.