Tehran explosion
© Twitter/Xinhua
An explosion in Iran has injured at least 39 people at the Grand Bazaar in central Tehran.

Al-Bawaba reports the likely cause of the blast as a faulty gas cylinder at a three-story building in Green Square. The fire department, though, said "the precise cause of the explosion is still not clear." They do believe the explosion happened on the first floor of the building. Financial Times reporter Monavar Khalaj says sources on the ground have dismissed terrorism as a possible reason for the explosion.

A spokesman for the Tehran fire department said some of the injured remain in critical condition.

Authorities are still on the scene and investigating the incident. The fire department asked people to "refrain from traveling in the area."

As of press time, Iran's major national English language state outlets PressTV and Tasnim News Agency have yet to report on the incident.

Translation: Tehran's police chief said chemicals for manufacturing firecrackers exploded in the marketplace.

Translation: Wednesday's victims

Local media said the area does not have any urban gas pipelines so people use domestic cylinders to heat their homes.