As many as 16  Chinese warships were spotted in waters around Taiwan in a 24-hour period late last week, media reports said on Monday.

The People’s Liberation Army Navy (PLAN) activity in the 24 hours ending at 6 a.m. local time Saturday followed exercises earlier last week that saw dozens of Chinese warplanes fly past the median line of the Taiwan Strait and into the key regions of Taiwan’s air defense identification zone (ADIZ), reports CNN.

Over 72 hours in the middle of last week, 73 PLA aircraft either crossed the Taiwan Strait’s median line – an informal demarcation point that Beijing does not recognize but until recently largely respected – or entered the southeastern or southwestern parts of the island’s ADIZ.

During that same period, nine PLA vessels were reported in waters around Taiwan in three consecutive days, reported the news channel.

“It is a growing military effort,” Carl Schuster, a Hawaii-based analyst and former director of operations at the US Pacific Command’s Joint Intelligence Center, told CNN on Monday.