One person was killed and several were injured in a roller coaster accident at the Grona Lund amusement park in the Swedish capital on Sunday, the TT news agency reported, citing a park spokesperson.
Public broadcaster SVT, citing eyewitnesses, said the park's Jetline roller coaster had partly derailed during a ride.
Police said they were still investigating.
"We are emptying the park and we've started our investigation," a police spokesperson said.
The Grona Lund park was not immediately available for comment.
The steel-tracked Jetline roller coaster reaches a speed of up to 90 kmph and a height of 30 metres, transporting more than one million visitors each year, the amusement park says on its website.


'Peace is not far away' says Erdogan after Putin meeting
Belarus frees Nobel winner, protest figures as US lifts more sanctions
Indonesia flood death toll exceeds 1,000
Ukraine's Odesa suffers major blackouts after Russian attack
Two killed in Ukrainian drone strike on Russia's Saratov
