CNN  — 

Twenty people – most of them teenagers – are now confirmed dead after a student went on a shooting spree and detonated a bomb at a college in Crimea, state-run Russian news agency TASS reported Thursday.

The suspected perpetrator also “shot himself dead” after the attack, said Crimean government head Sergey Aksyonov. The Crimean leader announced on Wednesday there would be three days of mourning.

The site of the attack at a college in the Crimean city of Kerch.

Crimea – a peninsula surrounded by the Black Sea and the Sea of Azov – was annexed by Russia from Ukraine in 2014.

Russia’s National Anti-Terrorism Committee told CNN that the blast was caused by an “unidentified explosive device” at a college in the city of Kerch – where a new 19-kilometer bridge links Crimea to Russia.

Russia’s Investigative Committee said in a statement: “According to preliminary data, an unidentified explosive device packed with metal objects went off today in the dining room of the Kerch Polytechnic College.”

It said information on the victims is being clarified and that “most of them are teenagers.”

Russia’s Investigative Committee said Wednesday it had identified the alleged perpetrator and classified the case as a murder investigation, after initially saying it could have been a terror attack.

The statement added that investigators and forensic experts carried out an initial examination of the bodies of the victims that indicated they died from gunshot wounds.

The families of the victims involved will receive compensation, the speaker of the regional parliament, Vladimir Konstantinov, told TASS.

A man lays flowers on the monument to the hero-city of Kerch in the Alexander Garden as a sign of mourning for those killed in the attack in Kerch, Crimea.

“Assistance will be provided to the relatives of those who died and those who suffered,” Konstantinov said, adding that preliminary discussions were underway about payments of 1 million rubles ($15,255) that would be allotted from the federal budget and 1 million rubles from the local budget to the family of each victim.

Medical workers treat injured people outside a college building in Kerch, Crimea.

Russian state media, quoting emergency-services officials, reported earlier that a suspected gas explosion at the technical college claimed several lives and injured dozens of people. State television channel Rossiya-24 said 200 military personnel had been sent to the site of the incident.