China’s military sent several dozen warplanes and warships toward Taiwan in a large-scale exercise that simulated sealing off the island in response to its president’s trip to the US.

The Chinese military earlier had announced three-day “combat readiness patrols” which it called Joint Sword, as a warning to Taiwan, a self-ruled island which China claims as its own. Beijing says contact between foreign officials and the island’s democratic government encourages Taiwanese who want formal independence, a step China’s ruling Communist Party says would lead to war.