Taylor Swift ’s upcoming concerts in Austria were the target of an alleged terror plot. Authorities in Vienna confirmed to NBC News Aug. 7 that two men have been arrested in connection to planned attacks targeting major events in the city, including the “Karma” singer’s upcoming Eras Tour shows on Aug.

8, Aug. 9, and Aug. 10, which have been cancelled.

One of the suspects taken into custody is a 19-year-old man who had allegedly pledged allegiance to the Salafi-jihadist group ISIS, Vienna State Police Director Franz Ruf and the head of the State Police Gerhard Purstl said during a press conference Aug. 7. The authorities also noted, per NBC News, another arrest was made later that afternoon.

Authorities explained that the arrested suspects had “detailed” plans to carry out an attack, and the 19-year-old had been found with chemical substances which authorities are currently trying to determine whether could be used to make a bomb. Swift’s upcoming shows at Ernst Happel Stadium have been canceled, according to a post shared by event organizers Barracuda Music shortly after authorities confirmed the arrests. Her website has since begun issuing refunds to ticketholders.

E! News has reached out to reps for Swift regarding the arrests and cancelation, but has not yet heard back. The arrest comes less than a month after an individual was arrested prior Swift’s concert in Gelsenkirchen, Germany, due to threats against Swift and her boyfriend Kansas City Chiefs tight .