U.S. and ROK troops carried out amphibious landing drills on South Korea’s east coast on Wednesday, as the allies ramp up joint exercises that they say seeks to ensure a “decisive combat” posture against North Korea’s military escalations.

The exercise featured around 30 allied vessels, including the USS Makin Island and ROKS Dokdo amphibious assault ships, and some 70 aircraft, including U.S. F-35B stealth fighters, Apache helicopters and ROK KF-16 and FA-50 jets.