TAIPEI (Taiwan News) — The Ministry of National Defense tracked 11 Chinese military aircraft and six naval vessels around Taiwan between 6 a.m. Tuesday and 6 a.m. Wednesday.

The ministry said 10 of the 11 People’s Liberation Army aircraft crossed the Taiwan Strait median line and entered Taiwan’s northern and southwestern air defense identification zone, or ADIZ.

The ministry monitored the situation, dispatched aircraft and naval vessels, and deployed land-based air defense missile systems in response.

So far this month, Taiwan has tracked Chinese military aircraft 502 times and ships 230 times. Since September 2020, Beijing has increased its use of “gray zone tactics” by operating military aircraft and naval vessels around Taiwan.

According to CSIS, gray zone tactics are “an effort or series of efforts beyond steady-state deterrence and assurance that attempts to achieve one’s security objectives without resorting to direct and sizable use of force.”