Around 18 people have been killed and over 50 wounded at a technical college in the small town of Kerch on the Crimean peninsula when an explosive device packed with metal fragments detonated on Wednesday, Oct. 17, Russian authorities stated.

“An unidentified bomb has exploded in Kerch,” said Andrei Przhezdomsky, the spokesman for the National Anti-Terrorism Committee of Russia.

Some eyewitnesses described a gunman haunting the halls of the school and shooting students and teachers before detonating a bomb in the college’s cafeteria.

The attacker, an 18-year-old Vladislav Roslyakov, carried a shotgun. According to Russian investigators, who identified Roslyakov as one of the students of the college, he killed himself at the site of the attack following the rampage.

The Investigative Committee had initially declared the assault a terrorist attack, but later requalified it as a “mass killing”.

Police have so far not commented on the incident. Russian media first reported the blast as the result of a gas explosion.

Vladimir Putin, President of the Russian Federation, expressed his condolences to the families and friends of victims. “It is clear that a crime took place. The motives and scenarios of this tragedy are being studied,” Mr. Putin said at a meeting with Egyptian President Abdul Fattah El Sisi in the Black Sea city of Sochi. He then asked for a moment of silence.