Three civilian planes flew in the restricted airspace Saturday, and there were four more violations on Sunday, NORAD said.

Military jets scrambled to intercept the civilian plane and used flares to alert the pilot, who was then escorted out of the area. It was the second such incursion on Sunday and one of five unauthorised entries into the restricted airspace over the weekend.

Fighter jets were scrambled to intercept a civilian aircraft after it entered airspace over Trump's Bedminster golf course on Sunday.