MOSCOW, April 24. /TASS/. The death toll from a fire at the Central Research Institute of Russia’s Aerospace Defense Force in Tver has increased to 17, a source in the emergency services told TASS on Sunday.

"As the debris continued to be cleared, another six bodies were found. The death toll from the fire is up to 17," the source said, adding that the scene of the incident continued to be searched.

The fire at the defense research institute occurred on Thursday to affect an area of 2.5 square kilometers. A total of 54 people were rescued from the building and 98 were evacuated. About 30 people were injured. According to preliminary findings, the fire was due to a power grid emergency. Also, the firefighters were called too late.

A criminal case was launched under part 3 of article 219 of the Criminal Code (violation of fire safety requirements, resulting in the death of two or more persons through negligence). Military investigators are probing into the case.