GROTON, Conn. (AP) — The Navy submarine base in Groton is marking Independence Day with a 21-gun salute.

The saluting battery will take place Wednesday at noon at the military base's weapons compound.

The event is not open to the public.

The military gives public notice about the event to avoid confusion over the source of the gunfire.

Single-round volleys will be fired at 30-second intervals until the 21-gun tribute is completed.