TAIPEI (Taiwan News) — The defense ministry detected 40 Chinese aircraft and six naval vessels between 6 a.m. on Friday and Saturday.

Twenty-seven of the aircraft reportedly crossed the median line of the Taiwan Strait and entered the nation’s central, southwestern, and eastern air defense identification zone, or ADIZ. In response, Taiwan sent aircraft and naval ships and deployed coastal-based missile systems to monitor Chinese activity.

This followed incursions from 50 Chinese military aircraft and six naval vessels around Taiwan between 6 a.m. on Thursday and 6 a.m. on Friday. Al Jazeera linked the rise in activity to the British Royal Navy vessel HMS Spey transiting the Taiwan Strait this week.

So far this month, Taiwan has tracked Chinese military aircraft 346 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.”