For at least two days this week China has conducted air drills off Taiwan’s southwestern coast, prompting angry condemnation and warning from the island that China claims as a breakaway territory.

According to Taiwan spokespersons, advanced People’s Liberation Army (PLA) Su-30 and J-10 fighters have conducted drills over the waters between Taiwan and Pratas Island, a small Taiwan-controlled feature in the South China Sea and intruded into its Air Defense Identification Zone (ADIZ). The Taiwanese military issued radio warnings to the Chinese planes until they departed the area.
Taiwan has been carrying out live-fire exercises of its own in the area involving long-range anti-air missiles.

Pratas Island is home to an air strip and a small mixed civilian and military population. The island lays more than two hundred nautical miles off Taiwan’s southwest coast in the South China Sea but is closer to mainland China, about 150 nautical miles southeast from Hong Kong. China claims Pratas as part of Guangdong Province.

https://thediplomat.com/2020/09/chinese-jets-intrude-taiwan-air-defense-zone-for-second-day/