The drill lasted for about 36 hours, the report said.

Zi Kun, an officer from the division’s training unit, said the drill was a test for both pilots and equipment because it involved planning and coordination to meet actual combat requirements.

The exercise came after the Eastern Theatre Command in early February launched joint drills featuring naval and air forces near Taiwan and a combat-readiness drill in which its warplanes encircled the self-ruled island.

It also came after the United States sent EP-3E Aries electronic warfare and reconnaissance aircraft to fly near Kaohsiung, in southern Taiwan, and Hong Kong in late March.

Beijing may step up drills in South China Sea amid US military tensions

Beijing views the self-governed Taiwan as a renegade province that must be united with mainland China by force if necessary.

Experts said the drill was designed to enhance China’s intelligence-gathering capabilities to better monitor activities at sea and in the air.

“The People’s Liberation Army’s Air Force used to rely only on ground-based early-warning radar. Only in the past two decades, it started to acquire airborne early-warning and control aircraft, which could allow the air force to extend their radar coverage beyond the limits of ground-based radars,” said Collin Koh, a research fellow from the S Rajaratnam School of International Studies at Singapore's Nanyang Technological University.

“The problem with ground-based radars is they are often limited by line of sight and Earth curvature, whereas the airborne early-warning assets can help to address these radar gaps and also have a better ability to pick up low-flying targets and those obscured by terrain,” Koh said.

Taiwan military stages exercise to fight off mock invasion

Zhou Chenming, a Beijing-based military expert, said that China did not have enough early-warning planes to support its expanding military ambitions and needed to maximise its capabilities through various exercises to act as a credible deterrent.

The command’s ongoing drills in recent months would be intended to send signals to the outside world on two fronts, according to Koh.

“The Eastern Theatre Command’s primary area of responsibility would cover Taiwan. And by extension, it also means targeting US forces concentrated not just in the nearby bases in Japan but also further afield beyond the First Island Chain, especially Guam,” he said.