TAIPEI (Taiwan News) — The defense ministry detected eight Chinese military aircraft, seven naval vessels, and two official ships around Taiwan between 6 a.m. on Friday and Saturday.

Three of the aircraft were reported to have crossed the median line of the Taiwan Strait and entered the country’s northern and southeastern air defense identification zone, or ADIZ. Three Chinese balloons were also detected.

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

So far this month, Taiwan has tracked Chinese military aircraft 361 times and ships 149 times. 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.

CSIS defines gray zone tactics 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.”