The incident is said to have taken place clost to the Tajrish Square, north of Tehran, with suggestions the building was a health centre. Those at the scene say the cause of the explosion is unknown. Newsweek reporter Tom O’Connor tweeted: “Following reports of an explosion at northern Tehran, Iran’s Tajrish Metro Station.”
Footage on social media showed plumes of black smoke rising high in the sky over the city, together with flames.
Midway through the clip there is a second, very loud blast.
Zillay Shah tweeted: “The cause of explosion is still not known.”
Journalist Kian Sharifi posted: “A spokesman for the fire department confirms to Fars news that a health care centre is on fire in northern Tehran, saying ‘people may be trapped inside’.”
Semi-official Iranian news agency ISNA has also reported on the explosions, without citing any additional information.
Jalal Maleki, the Tehran Fire Department spokesman, told the Tasnim news agency a fire had broken out in a medical clinic in north Tehran, with firefighters have been sent to the scene.
The head of the Tehran Emergency Center, Peyman Saberian, told the Fars news agency that three people have been injured.
The explosion comes days after another blast close to a sensitive military site near Tehran last week.
Speaking on state television, a defence ministry spokesman claimed it was caused by a tank leak at a gas storage facility.
However, there was also speculation that it was an accident at defence site belonging to the Islamic Revolutionary Guard Corps
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