Fresh commercial satellite images show that North Korea's sophisticated new missile base on its west coast — designed for multiple test flights in a short time — is ready for use, according to an independent U.S. analyst.

Photographic images show the launch tower and what appears to be construction materials on the launch pad, Tim Brown, a senior fellow with GlobalSecurity.org, said Thursday. He speculated that the debris may be there to make the pad appear as though it is still under construction.

"The launch pad appears to be operational," Brown said.

The satellite company DigitalGlobe produced the images Wednesday.

North Korea has been quietly building the new facility, which is capable of launching ICBMs, for nearly a decade. It represents a major step forward for its long-range missile program because the facility would allow multiple test flights in a short time, which is difficult at the smaller long-range missile launch site known as Musudan-ni on its east coast.

North Korea conducted an underground nuclear test on May 25. In March it launched a long-range missile that it claimed delivered a satellite into orbit.

The new launch facility is referred to as Tongchang-ri. It includes a movable launch pad and a 10-story tower capable of supporting North Korea's largest ballistic missiles and rockets. It also has a rocket motor test pad.