At least one person was killed and two were injured in an explosion that caused a fire at a building belonging to the border patrol of Russia's FSB security service in the southern city of Rostov-on-Don on Thursday, local authorities said.
Footage captured by Reuters showed a plume of thick black smoke billowing into the air, near residential buildings and a shopping center in a built-up district of the city.
Local emergency services said an explosion had occurred, igniting a fire that spread to an area covering 880 sq meters.
They said one person had been killed and two more injured in the incident.