The North American Aerospace Defense Command says two F-16 fighter planes intercepted an ultralight aircraft near the U.S.-Mexico border this morning.

The plane crossed from Mexico into Arizona just after 6 a.m. NORAD dispatched two F-16s from Tucson's Davis-Monthan Air Force Base and they shadowed the ultralight for about 30 minutes until it flew back into Mexico.

Lt. Cmdr. Gary Ross says he was unaware of any radio contact with the small plane.

Ultralight aircraft are sometimes used to carry drugs and other contraband across the border.

NORAD responds about 200 times a year to aircraft flying without radio contact or in restricted airspace, but Ross says it’s not typical for the command center to intercept an ultralight.

Ross could not provide further details about why F-16s were sent to intercept the aircraft.