A police officer discovered the bag at 9.40pm on Sunday evening at the Kungsträdgården park — one of the three sites of the then ongoing Stockholm Culture Festival.
Police then interrupted a concert taking place, and cordoned off Strömgatan, Strömbron and parts of the Kungsträdgårdsgatan park, while a bomb disposal squad came in to deal with the device.
“We took this extremely seriously right from the start,” Erik Åkerlund, local police chief in Stockholm’s Norrmalm district, told the DN newspaper. “There were a lot of people moving around, so we cordoned off a large area.”
According to the Aftonbladet newspaper, bomb technicians blew apart the bag at around 1am.
Åkerlund said that although the bomb contained explosives, it was too early to tell whether it was capable of being detonated.
Police have yet to identify or arrest a suspect, and are currently talking to witnesses and analysing the photo and video evidence people have sent in.
According to Linnea Monteiro, who is leading the Culture Festival, the stage at Carl XII square could not be used on Sunday night as it was within the police cordon, however the festival was able to continue at its other areas.