Four Russian military aircraft crossed the Alaska Air Defense Identification Zone on Monday, the North American Aerospace Defense Command said.
The four aircraft remained in international airspace and did not enter U.S. or Canadian sovereign airspace, NORAD said in a news release. There was no interception, it added.
“This Russian activity in the Alaska ADIZ occurs regularly and is not considered a threat,” NORAD said.
Monday’s incident was the fifth such incident since September, according to NORAD’s public statements about the detections. NORAD did not specify what type of Russian aircraft was involved. The command identified a Russian IL-38 maritime patrol aircraft inside the Alaska ADIZ earlier this month.
ADIZs begin at the edge of national airspace, in this case that of the United States and Canada. Such zones require “the immediate identification of all aircraft in the interest of national security,” NORAD said.
The command “employs a layered defense network of satellites, ground-based and airborne radars and fighter aircraft to track aircraft and inform appropriate actions,” it said in its news release.
“NORAD remains prepared to employ a number of response options to defend North America,” he added.