Alarms that a bus had rammed a bus shelter on Valhallavägen began arriving at SOS Alarm at 3:23 p.m.
Ambulances, fire engines and police are sent to the scene.
Many are at the accident site, which is located in a traffic hub with bus stops and stations for the metro and Roslagsbanan. The block includes the Royal Institute of Technology and Engelbrektsskolan, with a thousand primary school students.
Initially, several serious injuries were reported.
The emergency services state that the bus, a double-decker, was not in service and therefore without passengers.
Just under an hour after the first alarm, the police confirmed that several people had died.
The bus driver is arrested and the incident is initially classified as aggravated manslaughter.
Technicians will be on site this evening to examine the accident scene and secure any traces. The cause of the accident is not known.
During the evening, the City of Stockholm's crisis support team will be on site. The Kommunal union, which organizes employees at the affected bus depot, is deploying resources to support its members.
At 8:20 p.m., police confirmed that three people had died in the accident.
Four people, including the bus driver, are being treated in hospital, two of whom have serious injuries.
At 10 p.m., it was announced that the driver had been arrested on suspicion of causing death of a normal degree and causing bodily harm. According to the police, there is no indication that the incident was intentional.
On Saturday morning, police announced that the work of identifying the dead could take several days. One person is still considered to have serious, but not life-threatening, injuries.
On Saturday afternoon, the bus driver was released after questioning, but he remains a suspect in three cases of causing death and three cases of causing bodily harm.
