Beijing: China has started three days of military drills “around” Taiwan from Saturday, after the island’s president, Tsai Ing-wen, returned from US visits that infuriated Beijing.

The People’s Liberation Army announced the drills and patrols in airspace and waters on the north, south and east sides of Taiwan as “serious warnings” against Taiwan separatists in “collusion with external forces”.

In addition, a Chinese warship in seas facing the Taiwan Strait began live-fire drills on Saturday morning.

The amphibious landing ship – capable of transporting troops, craft and vehicles – fired multiple rounds of artillery in the Luoyan Bay area on the coast of Fujian province, about 50 kilometres north-west of the Matsu islands near the mainland that are controlled by Taiwan.

Eastern Theatre Command spokesman Senior Colonel Shi Yi said in a statement the exercises would last from April 8 to 10 and will be conducted “according to plan”.

He didn’t mention Tsai’s visits to New York and Los Angeles, which included meetings with House Speaker Kevin McCarthy and other US officials.

The Taiwanese Defence Ministry said it had detected 13 PLA aircraft and three vessels around the island in the 24 hours to Saturday morning, placing it on high alert to defend national security. Later it said more than 40 Chinese military planes briefly crossed the Taiwan Strait’s median line.

Beijing had pledged to respond to any meeting between Tsai and McCarthy, calling it a provocation that “damages China’s sovereignty and territorial integrity.” The latest planned drills appear to be on a smaller scale than exercises held by China after then-speaker Nancy Pelosi visited Taiwan last year, and didn’t include any imposition of exclusive zones in its airspace and waters.