Sweden’s Security Service office was evacuated Friday after a suspected gas leak that saw seven people treated at a hospital, authorities said, adding that the cause of the incident was unclear.
Images from the scene showed police officers wearing gas masks alongside several ambulances and emergency vehicles as an area around the office of the agency, known as Sapo, was closed off.
“Around 1 p.m. today, there were indications that there was a dangerous substance at Sapo’s offices,” said Patrik Soderberg, chief physician at the local health care authority Region Stockholm.
“So far, five people have been taken to hospital with respiratory symptoms, and there are also two people that have sought treatment on their own for respiratory symptoms,” Soderberg said.
He added that they did not immediately have information on what kind of substance they were dealing with.
Sapo spokeswoman Karin Lutz told AFP they had “taken measures and emergency services are on site” after receiving an alarm.
The Nordic country is on high alert as it is expecting to clear the final hurdle to its bid to join NATO on Monday, with the last holdout Hungary scheduled to vote on ratifying its membership.
Lutz said that the building had been “partly evacuated” but declined to give further details or comment on whether they suspected foul play.
Police said an area of “a couple of hundred meters” around the building had been closed off after “a potential gas leak.”
Police and emergency services were at the site, and some of those taken to the hospital were officers who had “smelled an odor when they arrived,” police said in a statement.
Around 4:30 pm, police said the operation had ended.
The Aftonbladet newspaper said that witnesses had reported smelling something that reminded them of paint and that locals had been told to close their windows.
The intelligence service this week released a report warning of the threat posed by foreign state actors, in particular Russia, China and Iran.