The Chinese People’s Liberation Army (PLA) held military drills featuring warplanes near Taiwan on Friday as part of “military struggle preparations against the island,” Chinese state media reported on Friday.

Global Times, a Communist Party propaganda newspaper, said multiple PLA warplanes – including H-6 bombers, KJ-500 early warning aircraft, and J-11 fighter jets – conducted a far-sea, long-range drill above southwestern waters near the island of Taiwan.

The PLA warplanes were seen flying over waters southwest of Taiwan and then entering the skies over the Bashi Channel – located between Taiwan and the Philippines – before returning to base via the same route, Taiwan’s Ministry of National Defense (MND) confirmed on Friday. Taiwan’s armed forces are closely monitoring the country’s surrounding waters and airspace, Taiwanese military spokesman Shih Shun-wen said.

Friday’s drill marks the sixth time this year that PLA aircraft have been recorded operating near Taiwan’s airspace, according to Taiwan’s MND.

On April 2, China’s PLA reported that the Chinese military command responsible for patrols around Taiwan staged a long-endurance, early-warning exercise in March. The drill was intended to simulate quickly countering enemy planes during wartime, a PLA officer said at the time.

In early February, China organized army-navy war games near Taiwan and surrounded the country with warplanes. Following days of drills, China’s PLA Eastern Theatre Command said its forces had carried out “air-ground assault and fire support drills to further refine and test their multi-service joint combat capabilities.”

In response, the United States recently sent military aircraft to operate near Taiwanese airspace to show support for Taiwan. The U.S. claims to be allied with Taiwan, but does not formally recognize that it is a sovereign state. On March 25, the U.S. sent EP-3E Aries electronic warfare and reconnaissance aircraft to fly near Kaohsiung, in southern Taiwan, and Hong Kong.

On Friday, Taiwan’s MND said it had also spotted a U.S. military reconnaissance aircraft flying near its airspace, with some suggesting that the U.S. may have been monitoring the unusual activity by the PLA warplanes in the area that same day.

China’s recent drills near Taiwan come after the U.S. signed the Taiwan Allies and International Protection and Enhancement Initiative (TAIPEI) Act into law on March 4, which enhances U.S. support for Taiwan. According to TAIPEI, the U.S. will reduce its economic, security, and diplomatic engagements with nations that take significant actions to undermine Taiwan, especially China.