One killed in Swedish roller coaster derailment

Children were among the seven injured at the Grona Lund amusement park in Stockholm

The Grona Lund amusement park in Stockholm after an incident on the Jetline roller coaster, where one person died AFP

One person was killed and seven were injured when a roller coaster derailed and sent people crashing to the ground at an amusement park in Sweden.

The incident happened at the Grona Lund attraction in Stockholm, and children were among the injured.

Witnesses said the park's Jetline roller coaster partially derailed during a ride.

Jenny Lagerstedt said she was nearby, heard a metallic sound then saw that the track was shaking.

"My husband saw a roller coaster car with people in it falling to the ground. My children were scared,” she told TV in Sweden.

The steel-tracked Jetline, which is 30 metres at its highest point, can reach a speed of up to 90kph.

Ambulances, fire vehicles and a helicopter arrived at the park, and police launched an investigation.

Police said there were children and adults among those injured but declined to comment on the extent of the injuries.

"This is tragic and shocking, and regrettably we've learned that one person has died," said Grona Lund spokeswoman Annika Troselius.

Sweden's Culture Minister Parisa Liljestrand offered her condolences to the victims of the incident.

"My thoughts are with those that were affected as well as their families and loved ones," Ms Liljestrand said.

The 140-year-old park was closed until further notice.

The roller coaster carried more than one million visitors each year, the amusement park's website says.