The blast occurred during Friday prayers inside a school complex in North Jakarta’s Kelapa Gading area.
An anti-bomb squad found toy rifles and a toy gun near the site as investigations into the cause continue.
Dozens of people were rushed to hospital following an explosion at a mosque in Indonesia’s capital, Jakarta, Al Jazeera reported.
The blast occurred during Friday prayers inside a school complex in Kelapa Gading, North Jakarta. City police chief Asep Edi Suheri stated that the cause of the explosion is still under investigation. Witnesses reported hearing two loud blasts around midday (04:00 GMT), just as the sermon had begun.
According to Suheri, 54 people, mostly students, were taken to hospital with injuries ranging from minor to severe, including burns. Twenty individuals remain under hospital care, with three in serious condition, he added.
An anti-bomb squad dispatched to the site discovered toy rifles and a toy gun near the mosque, Suheri said.
“Police are still investigating the scene to determine the cause of the blasts,” he explained.
Local television footage showed a police cordon around the school, with ambulances stationed nearby. Images of the mosque indicated that it had not sustained extensive damage.
(with inputs from Al Jazeera)
