A Pentagon spokesman confirms that an Air Force U-2 spy plane was conducting training operations in the area when an air traffic control computer failure grounded flights to and from Los Angeles-area airports last week.

Col. Steve Warren says, however, that it’s not unusual for a U-2 to operate in the region and the necessary paperwork and flight plan had been submitted. Warren added Monday that the high-flying spy plane’s operations were conducted according to plan.

Warren referred questions about Wednesday’s delays to the Federal Aviation Administration, and he says there’s no Air Force investigation.

The FAA has said there was a failure within the agency’s En Route Automation Modernization system at a facility north of Los Angeles. The system allows controllers to identify and direct planes at high altitudes.

(AP)