An 18-year-old youth has been jailed for 21 months, 10 suspended, for making a threat against prime minister Mark Rutte using the free online message service WhatsApp.

The youth sent a message to a friend in April 2014 threatening Rutte and another unnamed person. The threat eventually came to the attention of the prime minister, the Telegraaf reports, without giving details.

The youth, who was 17 at the time, said in his mail he knew Rutte cycled to work so it would be easy to get him. ‘I’ll get them all,’ he said. ‘Soon I’ll go outside and start shooting. I think I am psychotic. I think I am mad.’

Police found a gas pistol, ammunition and a silencer at the youth’s home.

The public prosecution department decided to prosecuted the youth as an adult because of the seriousness of the charges.