Anchorage police are warning Jewel Lake residents that they may hear a blast around 7:30 p.m. Wednesday, but only for a few seconds.
It'll be coming from a "flash bang demonstration" at the police training center near Dimond Boulevard and Jewel Lake Road, said police spokeswoman Jennifer Castro in an email.
Castro said the demonstration for the Citizens Police Academy will last less than five minutes. Officers typically use the grenade, a "flash bang," as a distraction device, she said. It emits a loud noise and bright light.
Overcast weather could increase the noise and vibrations from the grenade, Castro said.