China's secretive military appears to be up to something around Taiwan, but it's unclear whether it's a formal military drill. Taiwan's Defense Ministry said Tuesday that it has detected a dozen Chinese naval ships and 47 military planes in the past 24 hours but no live-fire activity as in previous military exercises.

The size and scale of a recent Chinese military deployment is “unheard of,” says a diplomat in the region. Beijing, which views Taiwan as its own territory, says it is defending its sovereignty.

The assessment contrasted with statements from Taiwan that described the deployments as the largest in nearly three decades. "The PRC military activity is elevated in the region, consistent with levels we have seen during other large exercises,

Taiwan is raising concerns about a massive deployment of Chinese naval ships and military planes in the past 24 hours, saying the build-up could eventually lead to war.