N Korean workers found dead in Russian shipping container

Five North Korean workers were found dead on Wednesday in a shipping container at a construction site in Russia's southern city of Ufa.

An official of Russia's Ministry of Emergency Situations confirmed the news, Yonhap agency reported.

The Russian media reported that the workers were presumed to have been killed by toxic gas from a coal fire, adding that they lit the coal fire due to a failure of the heating system in the shipping container where they lived.

The North Korean workers were working for Salviya, a Russian construction firm.

It is estimated that between 35,000 and 37,000 North Koreans work in Russia and are employed in various fields such as construction, logging, farming and fishing, making them a key source of hard currency for the communist country.