Taiwan's defense ministry says Chinese aircraft and vessels crossed the so-called median line on the Taiwan Strait on Friday morning during their military drills. The ministry condemned the move as "highly provocative."
The ministry said Taiwan's armed forces used alert broadcasts, aircraft, patrolling naval ships and land-based missile systems in response.
The Chinese military is holding exercises, including live-fire drills, in six areas surrounding Taiwan from Thursday through Sunday.
Taiwan's defense ministry said its forces seek no escalation nor conflict and are committed to protecting their land and its citizens.
The median line is an unofficial buffer to help prevent accidental clashes between Chinese and Taiwanese forces.
Chinese authorities have recently begun asserting that they do not recognize the line. Chinese fighter jets made cross-strait flights on Wednesday and Thursday.