A fire broke out at the Russian Aerospace Forces’ Central Research Institute Thursday in Tver, Russia, killing at least seven. Photo: Alisa Dovydenko/VCG

Smoke billows out of the burning building. The fire spread quickly from the second floor to the entire building, covering over 2,500 square meters. Photo: Maksim Shkolnikov/VCG

The roof of the building collapses during the fire. More than 25 injuries were injured, according to local authorities. Photo: Igor Stasyuk/VCG

Firefighters extinguish the fire through a high-pressure hose. Photo: Maksim Shkolnikov/VCG

A Mi-8 transport helicopter dumps water onto the burning building. Photo: Vitaliy Smolnikov/VCG

More than 240 firefighters, with over 69 sets of firefighting equipment, rushed to fight the fire, alongside health personnel in 14 ambulances. Photo: Maksim Shkolnikov/VCG

The charred façade of the military research facility. Photo: Maksim Shkolnikov/VCG

A preliminary investigation found that the fire might have been triggered by outdated electrical wiring in the building. Photo: Maksim Shkolnikov/VCG