San Diegans were startled by loud booms Tuesday night, with the first and loudest coming around 10:08 p.m.
Around the same time, low-flying aircraft could be seen flying around the Serra Mesa area, including from NBC 7 and Telemundo 20 studios.
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San Diego Police Department Lt. Adam Sharki confirmed the loud explosions heard across central San Diego were related to "preplanned, authorized military training" that took place near the now closed Fry's Electronics building in Serra Mesa.
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San Diego police were blocking Daley Center Drive near Stonecrest Boulevard to vehicles traveling in the area.
There were no other details available on when the training events would conclude.
