At least 10 people have died from methane poisoning while carrying out work at a water treatment plant in southern Russia, the state-run TASS news agency reported Friday.
TASS quoted an emergency services source in the city of Taganrog 1,000 kilometers south of Moscow as saying they were still searching for workers who may be trapped in the facility.
Accidents during water and sewage collector repairs are common but rarely lead to such a large number of victims, according to the state-run RIA Novosti news agency. The outlet said that warm weather causes a greater accumulation of toxic substances inside collection facilities, including nitrogen, methane, carbon dioxide, hydrogen sulfide and ammonia.
The regional news outlet 161.ru reported that authorities in Taganrog last summer promised to complete by 2021 large-scale reconstruction works at a pipeline that provides drinking water for 350,000 people.
Regional authorities allocated 82 million rubles ($1.1 million) for the works from the budget.