TAIPEI (Taiwan News) — The Ministry of National Defense (MND) tracked eight Chinese military aircraft and two naval vessels around Taiwan between 6 a.m. on Monday (Sept. 30) and 6 a.m. on Tuesday.

Of the eight People’s Liberation Army (PLA) aircraft, four crossed the Taiwan Strait median line in the country’s northern and southwestern air defense identification zone (ADIZ), according to the MND. 

In response, Taiwan sent aircraft and naval ships and deployed coastal-based missile systems to monitor PLA activity. 

Since September 2020, China has increased its use of gray zone tactics by incrementally increasing the number of military aircraft and naval vessels operating around Taiwan. 

Gray zone tactics are defined as “an effort or series of efforts beyond steady-state deterrence and assurance that attempts to achieve one’s security objectives without resort to direct and sizable use of force.”