Taylor Swift's canceled concert: Officials found explosives, detonators, and a stockpile of chemicals in a 19-year-old's home

• Officials said a 19-year-old male planned to use knives and explosives at a Taylor Swift concert.
• He and another 17-year-old male are believed to have been radicalized by ISIS, authorities said.
• They were in contact with other people who knew about the attack, an Austrian official said.

Austrian officials said they arrested three male teenagers on Wednesday on suspicion of planning an attack on a Taylor Swift concert in Vienna, the threat of which prompted organizers to cancel three of the singer's shows.