The tragedy in a college in the Crimean city of Kerch will be thoroughly analyzed to hammer out effective measures to reduce the risk of their recurrence, Russian Presidential Spokesman Dmitry Peskov told reporters when asked whether urgent measures were needed to prevent such incidents in the future.

"Emotionally, such reaction is understandable, but first we will have to carefully look into the circumstances, establish the details of this tragic mass shooting, and only after that the experts should forecast certain actions," Peskov said, describing the Crimea college attack as a very dangerous trend.

"We need to take effective measures to minimize, if not completely eliminate such risks in the future," the Kremlin spokesman stressed. "Such momentary impulsive actions are explicable, but they are unlikely to help, a comprehensive approach is required."

On Wednesday, a local student, armed with a rifle, went on a shooting rampage and detonated a bomb on the campus of the Kerch Polytechnic College in Crimea. The shooter later turned the gun on himself and committed suicide. Subsequently, a criminal case was initially opened on terrorism charges, but was later reclassified as murder.

Twenty-one people died because of the shooting and explosion at the Kerch technical college, including the gun-wielding teenage attacker who ended up taking his own life. Around 50 people were taken to local hospitals, with ten of them in intensive care units in grave condition.

Three days of mourning have been declared in Crimea as of Thursday.