A third suspect has been arrested in connection with a plot to “kill as many people as possible” outside a Taylor Swift concert in Vienna. Wednesday Austrian authorities arrested a 19-year-old who had sworn allegiance to the Islamic State and a 17-year-old who had materials from the organization in his home. The latter had recently gotten a job with a company that staffs Vienna’s Ernst-Happel-Stadion during concerts.

Now a third teenager is in custody. As the Associated Press reports, an 18-year-old Iraqi citizen was arrested Thursday night. As previously reported, a 15-year-old was also questioned but not arrested. The names of the suspects have not been released.

All three of Swift’s scheduled shows in Vienna this weekend, set for Thursday, Friday, and Saturday, were canceled after news of the foiled terror plot broke. Fans gathered in the streets of Vienna Thursday to sing songs, trade friendship bracelets, and lament the cancellations.