Chinese forces tested their ability to deploy ballistic missiles designed to strike U.S. aircraft carriers, as Beijing raises the specter of an invasion of neighboring Taiwan in response to a recent visit to the island by three U.S. senators.

“We have been holding night exercises on a regular basis recently, which usually continues until early the next day,” People’s Liberation Army Col. Jiang Feng said of the Tuesday drills, according to regional media. “We often change training grounds, striking targets, and launch bases without prior notice to test the troops’ skills and pave the way for the brigade to fight and be able to fight at any time.”