One worker has died and six others are injured after a fire at a chemical plant in southern Russia, authorities have said.
The accident occurred on Thursday evening in a workshop at the Kamenski factory in the Rostov region.
At least one person had died of burns, according to a statement from the state-owned company.
The fire was quickly brought under control and "no harmful substances were released into the atmosphere", the statement said.
The victims were hospitalised in the Kamensk-Chakhtinski city hospital and "are in a very serious condition".
Interfax news agency has reported that "insufficiently qualified" workers had "unintentionally transgressed" safety rules when processing chemicals.
The Kamenski factory officially produces "special-purpose chemical products" for the Russian army, aimed at "strengthening the country's defensive capabilities", according to the company's website.
It also produces a wide range of chemicals for civilian use, such as antifreeze and sodium salt CMC.
A government investigation commission on the accident has been set up, headed by the department for conventional weapons, ammunition and special chemicals in the Russian Ministry of Industry and Trade.
"The technological operation during which the fire broke out is highly automated and does not involve the presence of humans in the workshop," the ministry said in a statement sent to AFP.