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Austrian authorities on Friday announced a third arrest in connection with the foiled conspiracy to attack three now-cancelled Taylor Swift concerts, even as disappointed fans charmed Vienna by trading friendship bracelets and singing the pop star's songs in the streets.
The main suspect, a 19-year-old, planned to target onlookers gathered outside Ernst Happel Stadium — up to 30,000 each night, with another 65,000 inside the venue — with knives or homemade explosives during the concert on Thursday or Friday.
The suspect hoped to "kill as many people as possible," authorities said.
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The 19-year-old main suspect was taken into custody on Tuesday, along with a 17-year-old, officials said. Both are Austrian citizens.
The third suspect, an 18-year-old Iraqi citizen, was arrested on Thursday evening, the interior minister said at an unrelated news conference on Friday.
A 15-year-old was also interrogated but was not arrested. Their names were not released, in line with Austrian privacy rules.
Swift is still set to travel to London's Wembley stadium for five concerts between August 15 and 20 to close the European leg of her record-setting Eras Tour.
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London Mayor Sadiq Khan said that while he understood Vienna's reasons for cancelling, "We're going to carry on".
Still, the Vienna plot drew comparisons to a 2017 attack by a suicide bomber at an Ariana Grande concert in Manchester, England, that killed 22 people.
The bomb detonated at the end of Grande's concert as thousands of young fans were leaving, becoming the deadliest extremist attack in the United Kingdom in recent years.
Coldplay is scheduled to play four nights at the same Vienna stadium later this month.
Authorities said the scheme was inspired by the Islamic State group and al-Qaida. The main suspect, as well as the 18-year-old arrested on Friday, pledged "an oath of allegiance" to the Islamic State group.
Investigators discovered bomb-making materials at the main suspect's home, as well as Islamic State group and al-Qaida material at the 17-year-old's home.
That suspect, who has so far refused to talk, was employed a few days ago by a company providing unspecified services at the venue for the concerts.
Although the 18-year-old swore the oath and "comes from the social environment" of the main suspect, Interior Minister Gerhard Karner said, he is not directly linked to the plot.
The Austrian Interior Ministry, in a statement on Friday to The Associated Press, said "his arrest underscores the broad scope of the on-going investigation. Authorities are taking decisive action against anyone who might be involved in terrorist activities or exhibits radical tendencies".
Investigators are scrutinising the "networks" of the suspects, the statement said, and have turned to evaluating physical and electronic evidence.
Shiraz Maher, an expert on Islamic extremism with the Department of War Studies at King's College London, said in a statement to the AP that attackers "prioritise casualties and therefore choose soft targets where they know large numbers of people will be congregating."
Concert organiser Barracuda Music said it cancelled the three-night Eras Tour run, scheduled to begin on Thursday, because the arrests were too close to showtime.
Heartbroken Swifties consoled each other on social media and in the streets of Vienna. After travelling from across the globe, hundreds gathered on Corneliusgasse, a small street just 5 kilometres from the stadium whose name echoes that of "Cornelia Street," a contemplative synth-pop track from Swift's 2019 album, Lover.
They sang Swift's top hits, took selfies and traded friendship bracelets. Swift fans often swap the beaded bracelets, typically bearing Swift's song titles or popular phrases, with strangers at her concerts.
Even as the fans belted out her lyrics, the superstar has not spoken publicly about the plot or cancelled shows.
"Taylor Nation," a verified Instagram page widely believed to be run by her team, reposted the announcement from Barracuda Music, while her main account has not posted anything.
Last month, when a suspect in England killed three girls and wounded 10 people in a knife attack during a Taylor Swift-themed dance and yoga class, the performer said she was ''completely in shock'' over the violence.
