JAKARTA, Indonesia (AP) — Indonesian authorities said they have identified a 17-year-old boy as the suspected perpetrator of an attack that shook a mosque at a high school during Friday prayers in the capital, Jakarta , injuring at least 54 people, mostly students.

Witnesses told local television stations that they heard at least two loud blasts around midday, just as the sermon had started, from inside and outside the mosque at SMA 72, a state high school within a navy compound in Jakarta’s northern Kelapa Gading neighborhood.

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