The 19-year-old, originally from North Macedonia, confessed to all of his crimes while in custody, Austrian Director General of Public Security Franz Ruf told a news conference.

Ruf added that he had pledged allegiance to the leader of the IS group on the internet. The young man had chemicals, machetes and technical equipment at his home in the town of Ternitz to prepare for an attack.

The suspect had planned a suicide attack on some 20,000 fans gathered outside Vienna's Ernst Happel Stadium during the music event, according to national intelligence chief Omar Haijawi-Pirchner. Two other Austrian men, aged 15 and 17, were also arrested on Wednesday in connection with the plot.

"The main plotter has confessed that he intended to carry out a suicide attack together with two accomplices," Austrian Chancellor Karl Nehammer said. "The real suspects had very specific and detailed plans... to cause a bloodbath."

Authorities have painted a picture of the prime suspect as self-radicalizing, changing his appearance and sharing Islamist propaganda online. He quit his job on July 25, telling people he had “big plans.”

A neighbor told Austrian television station Puls24 that the suspect had kept to himself and had a “Taliban beard.” Security officials said the 17-year-old had only been hired by a company providing services at the stadium a few days ago.

Event organizer Barracuda Music said it had canceled Swift's three shows in Vienna, which were scheduled to start on Thursday and each had an audience of 65,000. Many fans who had traveled all the way to Vienna expressed disappointment and sympathy.

"It's heartbreaking and disappointing. But at the end of the day, I think it's for everyone's safety," said Mark del Rosario, who flew in from the Philippines to see the hugely popular American singer in concert.

US television station ABC cited law enforcement and intelligence sources as saying that Austrian authorities had received information about a threat to Swift's concert from US intelligence.

Austrian Interior Minister Gerhard Karner said foreign intelligence agencies were assisting in the investigation because Austrian law does not allow monitoring of messaging apps.

British police said on Thursday there was no indication the planned attack in Vienna would affect Swift's performance at London's Wembley Stadium next week.

Bui Huy (according to Reuters)