A chemical leak in Volokolamsk, Russia, has hospitalised 180 people - including schoolchildren. Young children were rushed to hospital from their school following the leak. Teachers in the town, around 80 miles from Moscow, called doctors when more than 20 pupils became unwell in class. They were later taken to hospital, where a huge crowd of around 180 people were waiting to be treated. All were suffering from nausea and headaches after a chemical leak from a nearby dump. Russian news agency TASS said: "More than 20 pupils were hospitalised, presumably after a strong release of hydrogen sulfide at the Yadrovo dump." They said a source told them: "The teachers noticed the children began to feel unwell and called the doctors. "There was a sharp smell of hydrogen sulfide." The situation is now under control. It comes after huge protests about the state of air pollution in the city. On March 8 demonstrators blocked a road leading to the toxic dump, leading to nine arrests. Radio Free Europe said 5,000 people took to the streets, with local officials eventually promising "to modernise" the facility. The site was opened in 2008 to provide a dumping site for residents in Moscow and nearby regions.