A suspected gas leak was detected at the headquarters of SAPO, Sweden's security agency, on Friday (Feb. 23), forcing authorities to evacuate some 500 people from the facility in Solna, north of Stockholm.

Police spokesperson Anders Bryngelsson told the TT news agency that emergency services dedicated to evacuating the entire building because of a "suspected gas leak" were called to the scene but did not elaborate further.

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At least five people suffered breathing problems and were taken to hospital, according to Stockholm physician Patrik Söderberg.

Images shared from the scene showed first responders and police officers wearing gas masks, and local media reported that a 500-meter diameter buffer zone was proactively set up to keep people out.

Authorities also told residents near the SAPO headquarters to close their windows, the Associated Press reported.

This is a developing story. Please follow HNGN for more updates.

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