"39 PLA aircraft and 3 PLAN vessels around Taiwan were detected by 6 a.m.(UTC+8) today. R.O.C. Armed Forces have monitored the situation and tasked CAP aircraft, Navy vessels, and land-based missile systems to respond these activities," the ministry said on Twitter.
According to the ministry, 21 J-16 fighters, one CH-4 unmanned aerial vehicle, two KJ-500 airborne early warning aircraft, one Y-20 cargo aircraft, one Z-9 utility helicopter, and four H-6 jet bombers crossed the median line of the Taiwan Strait.
Taiwan sent an air patrol to monitor the situation, issued radio warnings, and deployed anti-aircraft missile systems, the ministry added.
The situation around Taiwan escalated after US House Speaker Nancy Pelosi visited the island in early August. China condemned Pelosi's trip, which it regarded as a gesture of support for separatism, and launched large-scale military exercises in the vicinity of the island.
Several countries, including France, Lithuania, the United States, Japan, and most recently Germany have sent their delegations to the island since then, further increasing tensions in the Taiwan Strait.
Taiwan has been governed independently from mainland China since 1949. Beijing views the island as its province, while Taiwan — a territory with its own elected government — maintains that it is an autonomous country but stops short of declaring independence. Beijing opposes any official contacts of foreign states with Taipei and considers Chinese sovereignty over the island indisputable.