WASHINGTON, May 1 (Xinhua) -- SpaceX launched a spy satellite for the U.S. Department of Defense early Monday morning and then landed the first stage of its rocket back on solid ground.

The two-stage Falcon 9 rocket, carrying the classified NROL-76 satellite, lifted off at 7:15 a.m. EDT (1115 GMT) from historic Launch Complex 39A at Kennedy Space Center in Florida, the same pad that supported numerous Apollo and space shuttle launches, the company's live webcast showed.

About 10 minutes later, the rocket's first stage landed at SpaceX's Landing Zone 1, just south of the launch site at Cape Canaveral Air Force Station.

SpaceX previously landed a first stage booster at Landing Zone 1 three times. It also successfully recovered Falcon 9 first stages from six missions at sea using the company's drone ships.

Few details have been released about NROL-76, a satellite designed, built and operated by the National Reconnaissance Office, a member of the U.S. intelligence community of an agency of the U.S. Department of Defense.

This launch has great symbolic significance for SpaceX, since it's the 15-year-old company's first mission for the Pentagon.

For years, the market for launching U.S. military payloads was dominated by the United Launch Alliance, a joint venture of Lockheed Martin and Boeing.

But SpaceX broke the monopoly in 2015, when the U.S. Air Force certified its Falcon 9 rocket to launch national security space missions.

Since then, the California-based company has also won two contracts to launch Global Positioning System satellites for the U.S. Air Force.