A bomber of the Eastern Theater Command of China's PLA is seen during a combat readiness patrol and military exercises on April 8, 2023 (AP)

Taipei authorities on Sunday said that China deployed 28 warplanes around Taiwan, with the majority 'breaching' the median line in the Taiwan Strait for undisclosed "long-range" purposes.

The Defense Ministry stated that 20 of these aircraft crossed the median line, entering both the southeast and southwest air defense identification zones of the island.

China was engaged in activities like extensive exercises and training, and they are closely monitoring the situation using patrol aircraft and ships, according to the Ministry.

國防部 @MoNDefense 表示，今日上午陸續偵獲中共殲-10、殲-16、轟六、空警-500、運-9、運油-20及彩虹4無人機等各型機計28架次出海活動，其中20架次逾越海峽中線及其延伸線，進入我西南及東南空域，執行遠海長航等演訓任務。
國防部強調，國軍運用 #聯合情監偵手段…
— 軍聞社 Military News Agency, ROC(Taiwan)🇹🇼 (@mna_roc) September 17, 2023

A week ago, Taipei said it observed an increase in the number of 'incursions' by Chinese warplanes and naval vessels. This reportedly followed Beijing's statement that its forces were on "high alert" in response to two ships from the US and Canada trespassing through the Taiwan Strait earlier in the month.

Taiwan's Defense Ministry reported the detection of 68 Chinese aircraft and 10 naval vessels around the island between Wednesday morning and Thursday morning.

Some of these planes and warships were en route to an unspecified location in the Western Pacific for the purpose of "joint sea and air training" with China's Shandong aircraft carrier, according to the Ministry.

Taipei authorities also said they observed the Shandong, one of the two operational aircraft carriers in the Chinese fleet, approximately 60 nautical miles (110 kilometers) southeast of Taiwan, heading toward the Western Pacific on Monday.

As of now, China has not officially commented on any drills taking place in the Western Pacific.

The situation around Taiwan escalated following former US House Speaker Nancy Pelosi's visit to Taipei last year.

China considers Taiwan part of its territory and opposes any direct official foreign contact with the island.

Pelosi's visit led China to announce ending cooperation with the United States on a number of issues such as climate change, anti-drug efforts, and military talks.

Earlier this year, China vowed to "fight resolutely against so-called Taiwan independence, promote the peaceful development of relations between the two sides of the Taiwan Strait, and advance the peaceful reunification of the homeland."