However, a source close to the construction told the Global Times it was merely a renovation on the infrastructure of the reef.
A dozen photos were posted on nhjd.net, an unofficial discussion board for studies of the South China Sea, by the forum's administrator Friday.
The photos show trucks and cranes at a construction site and several engineering vessels. One of the photos shows Chinese warships near the construction site. Another photo shows vessels flying Vietnamese flags nearby.
After being posted online, the photos soon went viral.
On March 14, 1988, China and Vietnam fought a small-scale conflict for the Chigua Reef, which led to China's control of the reef.
A source told the Global Times China is renovating the living facilities for troops stationed on the reef, and the renovation could by no means be comparable to construction made on occupied reefs and islets by Vietnam and the Philippines.
The source further noted that China's construction on reefs and islets under its control has always been "restrained."
The Chigua Reef is now administered by the city of Sansha, Hainan Province, which was established in 2012.(Information : sina)