China's 'dangerous position'

The map, one of several in the report depicting Chinese forces, shows the current claims in the Spratly Islands as well as China's facilities there.

The territorial and continental shelf claims of China, Indonesia, Malaysia, the Philippines, and Vietnam are shown with several overlapping lines. The map also gives rough locations for seven Chinese outposts, including three airfields, and 63 other outposts in the Spratlys.

China's outposts "are capable of supporting military operations" and "have supported non-combat aircraft," the Pentagon report says. "However, no large-scale presence of combat aircraft has been yet observed there."

The report also says the missiles and other weapons systems at Chinese-controlled outposts are "the most capable land-based weapons systems deployed by any claimant in the disputed South China Sea to date."

Chinese military operations in the South China Sea are overseen by the Southern Theater Command, which is one of China's largest and most important theater commands.