A pregnant woman is among at least 22 people killed after a fire tore through an office in Indonesia.

The seven-storey building in the capital, Jakarta, was engulfed by flames earlier today.

Authorities believe the fire, which broke out in the neighbourhood of Kemayoran and took three hours to extinguish, started on the first floor before spreading.

Hundreds of firefighters scrambled to the scene of the blaze, the cause of which is still under investigation.

Many workers in the building, used as a sales and storage office for a drone company, were out for lunch at the time.

Image: Authorities said the fire started on the first floor. Pic: AP/Dita Alangkara

Central Jakarta police chief Susatyo Purnomo Condro said a battery started sparking in a storage and testing area, according to

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