Taiwan's defense ministry says 11 Chinese military aircraft crossed the median line in the Taiwan Strait on Thursday. The line is an unofficial buffer to prevent unintended military clashes between Taiwan and China.

The ministry says it detected 21 planes and six vessels from the Chinese military in and around the Taiwan Strait by 5 p.m. on Thursday. It adds that 11 of the aircraft flew on the eastern side of the median line.

Chinese military aircraft have ventured across the line every day since August 3. Such flights had rarely been observed until last month.

The latest crossings came after China on Wednesday announced the end of large-scale military drills around Taiwan. The exercises began last week following US House Speaker Nancy Pelosi's visit to Taiwan.

Analysts say the daily crossings show China's intention to increase pressure on Taiwan by making such flights routine.

Meanwhile, Taiwan's President Tsai Ing-wen visited the air force's command headquarters on Thursday.

Tsai said she is grateful to the air force for its commitment to protecting Taiwan's airspace and its people's safety day and night.

She said she wants the military to demonstrate to the whole world its determination never to yield even a tiny part of Taiwan's territory or to back down in its efforts to safeguard freedom and democracy.