An explosion and fire in a medical facility in the north of the Iranian capital killed 18 people, according to Press TV.
Earlier, the head of Tehran's ambulance service, Peyman Saberian, told Fars news agency that the death toll from the blast was 13.
Six people were injured, Saberian reportedly said.
People have been sharing videos on social networks of a building on fire - reportedly the Sina Athar Medical clinic.
There's not yet any official information on the cause of the incident or on possible casualties.
#BREAKING— Kamsin Sallar (@Kamsin_Sallar_) June 30, 2020
2nd attack in a single day in Iran.
As per reports :
Multiple explosions heard in Iran, near Tajrish square, north of #Tehran.
The cause of the explosion is still unknown but attackers hit Sina Athar hospital, casualties also reported.#Iran #Tehran pic.twitter.com/5tpEBjZbLH
Commenting on the incident, Jalal Maleki, the Tehran Fire Department spokesman, said as quoted by the Tasnim news agency that a fire had broken out in a medical clinic and firefighters have been sent to the scene.
صدای انفجار بزرگی از بیمارستان سینا اطهر در محدوده خیابان شریعتی نرسیده به تجریش به گوش رسید و الان هم این بیمارستان داره توی آتیش میسوزه در حالی که مردم محلی میگن بیمار توی بیمارستان هست.#تجریش #آتشسوزیهای_زنجیرهای #آتش pic.twitter.com/SgoCfDLZBC— Mahtab Gholizadeh (@mahtabgholizade) June 30, 2020
According to Iranian Fars News Agency, preliminary suspicions indicate that an oxygen tank was behind the blast.
The explosion occurred in the underground floors of the building which caused smoke to rise up through the floors, the agency reported, adding that firefighters have been able to localize the fire.
The incident comes several days after a large explosion occurred east of Tehran. According to the Iranian Defense Ministry spokesman, the incident was a gas tank explosion with no casualties being reported.