The 19-year-old has been convicted of preparing to commit murder, the BBC reports. The sentence will be announced by the judge at a later date. According to the verdict, he was to shoot an unidentified person.
The teenager was arrested in a hotel room in Huddersfield in March last year. Two guns and ammunition were found in the room.
Prosecutor Alistair Richardson has said that the teenager was recruited by the Foxtrot network.
