China is building capabilities that put most U.S. space assets at risk, said the head of U.S. Space Command, Gen. Dickinson, Reuters reports.

Beijing has made significant advances in recent years that have alarmed Washington and other Western nations, including an anti-satellite missile test in 2007.

Dickinson said such anti-satellite or anti-satellite tests fill space with debris. "They continue to build and build capabilities that really, quite frankly, hold most of our assets at risk in the space domain. It really is an advancement if you will in their capabilities," he said, referring to China. "Their understanding (is) that space is a very important piece to not only their economic or the global economic environment but also the military environment. We continue to watch that very closely as they continue to increase capabilities."

China says its space program is for peaceful purposes.

Three Chinese astronauts landed Sunday aboard the Shenzhou-14 spacecraft's reentry capsule, state broadcaster CCTV reported, completing a six-month mission to the Chinese space station. The station represents a milestone in China's three-decade-long manned space program, first approved in 1992. It also marks the beginning of a permanent Chinese presence in space.