The police have tracked down a 36-year-old man believed to be responsible for an online comment threatening a school shooting attack that caused a considerable amount of alarm, heightened security around schools and criticism of the police in early April.

The threat was made on 2 April in the comment section on the news portal 24ur under a news article about the deadly school shooting in Finland that day.

The portal immediately deleted the comment and alerted the police, but later, when the police said they had no legal basis to track the author, revealed publicly that the user named Slava_Rusiji (Glory_to Russia) wrote: "And on 10 April it will happen here".

Nearly a week after the threat was made, the police called on schools to be vigilant and increase self-protective behaviour but said such an event was unlikely.

Most of the schools beefed up security on the day of the suggested attack and police increased presence around schools, while many students stayed home. The police earned criticism for how they handled the threat.

On 23 May the Ljubljana Police Department announced they had filed a criminal complaint against a 36-year-old they believe wrote the comment and caused unnecessary alarm.

The police seized several electronic devices and live ammunition during a search at the suspect's home, unofficially in a village near the north-eastern city of Murska Sobota.

The suspect falsely reported that there was a risk of danger, causing the authorities to take unnecessary action, which is a crime carrying a prison sentence of up to five years. The damage he caused with the post is estimated at €70,000.

The suspect also faces proceedings over violation of the arms act.

He has had run-ins with the police before for attempting to obstruct an official act or taking revenge against an official.