New satellite imagery appears to confirm a report earlier this week that China has nearly completed structures intended to house surface-to-air missile systems on its three largest outposts in the disputed Spratly chain of the South China Sea — "part of a steady pattern of Chinese militarization" there.

The imagery, released by the Asia Maritime Transparency Initiative at the Center for Strategic and International Studies (CSIS), shows structures being installed on Fiery Cross Reef, Mischief Reef and Subi Reef — man-made islands dredged by China that are all home to military-grade airfields.

The group said construction on the buildings was believed to have begun between late September and early November last year, with eight of the buildings being constructed on each of the three outposts.