Tram derails, crashes into Oslo shop injuring four

A tram has derailed and crashed into a store in central Oslo, injuring the driver and at least three other people, Norwegian police said.

Emergency services treated the wounded at the scene but none were believed to have severe injuries, police said, adding there were around 20 passengers on board the tram at the time of Tuesday's collision.

The blue tram of the Oslo transport authority Sporveien left the tracks and collided with a computer store on the ground floor of a four-story building in the centre of the Norwegian capital.

It derailed as it was making a left turn into Storgata, one of the main streets in central Oslo, said Anders Roenning, the police officer in charge of operations at the scene.

"Instead it drove straight and right into the shop," he told Reuters.

Demolition worker Thomas Larsen, 41, was on an electric scooter driving towards the tram when it derailed in front of him.

"I hit the brakes. Three seconds later, I would have been under it," he told Reuters.

"It is scary that this could happen in the middle of the city."

It is too early to say what caused the incident, a Sporveien spokesperson said. "We are going to have to conduct inquiries on site by our specialists."

The crash triggered a massive response by rescue services. The area was cordoned off and the building was evacuated. It will be inspected for structural damage, police said.