Taiwan's defense ministry said on Sunday that over the previous 24 hours it had detected eight Chinese fighter jets crossing over the median line of the Taiwan Strait, as well as one Chinese balloon.
Taiwan, which China claims as its own territory, has repeatedly complained of Chinese military activity around the island over the past four years.
China has been stepping up its missions near Taiwan as the January 13 presidential and parliamentary elections on the island approach.
Taiwan's defense ministry said the Chinese J-10, J-11 and J-16 fighter jets had crossed the median line at points to the north and center of the strait.
The median line once served as an unofficial barrier between the two sides, but Chinese planes now regularly fly over it.
Taiwan also reported Chinese balloon
Taiwan sent its own forces to monitor, the ministry said.
The ministry also reported another Chinese balloon in the strait, the latest in a spate of what Taiwan says are most likely for monitoring the weather, driven by prevailing winds at this time of year.
It said the balloon was spotted after crossing the median line late on Saturday morning 97 nautical miles (180 km) northwest of the northern Taiwanese port city of Keelung at altitude of approximately 20,000 feet (6,100 metres).
The balloon headed east and disappeared around one hour later, the ministry added.
The potential for China to use balloons for spying became a global issue in February when the United States shot down what it said was a Chinese surveillance balloon. China said the balloon was a civilian craft that accidentally drifted astray.