Cheers erupted from SpaceX mission control as one of its Falcon 9 rockets - carrying a classified payload known only as NROL-76 - successfully launched from Cape Canaveral in the US state of Florida on Monday.

It was the first time the aerospace manufacturing company has launched a rocket for the US military - carrying a payload for the National Reconnaissance Office, which makes and operates spy satellites for the United States.

No details were divulged about the satellite after the launch. Instead, SpaceX focused its webcast on the landing of its first-stage booster.

A few minutes after the launch, a tall portion of the rocket flew back to Earth and made a successful controlled landing at Cape Canaveral.

A new (and classified) frontier

Until now, the US military has worked exclusively with United Launch Alliance - a joint operation between aerospace giants Boeing and Lockheed Martin - to launch government satellites.

In 2014, SpaceX filed suit against the US Air Force, arguing that it unfairly awarded billions of dollars to a single company.

The aerospace company has also landed a pair of launch contracts for the US Air Force to send GPS satellites into orbit.

Sunday's launch is part of SpaceX's efforts to make rockets recyclable rather than discarding the expensive parts after each launch.

The California-based company, led by entrepreneur Elon Musk, has already completed several successful rocket landings on platforms floating in the ocean and on solid ground.

rs/tj   (AP, AFP)