Russia has reportedly used hypersonic missiles in combat against Ukraine last week, marking the first known use of the new superweapons in combat by any military.

“US officials confirmed to CNN that Russia launched hypersonic missiles against Ukraine last week, the first known use of such missiles in combat,” CNN reported. “The launches were likely intended to test the weapons and send a message to the West about Russian capabilities.”

Hypersonic missiles travel at five times the speed of sound or faster, have lower trajectories than ballistic missiles, and can maneuver before hitting their intended target, which makes it hard to shoot them down.