Four persons have been killed in a blast on the territory of public joint-stock company Zaporizhkoks in Zaporizhia on Thursday, the press service of the police department of Zaporizhia region has told Interfax-Ukraine.

"A tank with gas has blasted at the plant. Four contract employees who were welding the tank have been killed. Three persons were found dead at the side and one more died in the ambulance," the press service said.

The police received the report about the blast at around 15:15.

Emergency response group, doctors and the police are working at the scene.