JERUSALEM - Israel's military said on Friday its missile defences had been triggered by an unmanned aircraft that crossed into Israel from Lebanon.

Moments earlier air raid sirens sounded in the Galilee region of northern Israel, warning residents to take cover. There were no immediate reports of injuries or damage.

"Iron Dome interceptors were launched according to protocol and fighter jets were scrambled to patrol the area. No special instructions for civilians in the area have been issued," the military said in a statement.

On Thursday the military said it had downed a drone that belonged to the Lebanese militant group Hezbollah after it crossed into Israeli air space.

(Reporting by Ari Rabinovitch Editing by Mark Heinrich) ((; +972-2-632-2202; Reuters Messaging: