Defense personnel from Japan, the United States and South Korea have wrapped up their newly launched joint exercise.
The three-day Freedom Edge exercise that ended on Saturday was conducted in the East China Sea and elsewhere.
South Korea's Joint Chiefs of Staff says seven types of drills were held, including a missile defense operation at sea and responding to a cyberattack.
Images released by the US Navy on Friday show MH-60 helicopters and FA-18 fighter jets taking off and landing on the nuclear-powered aircraft carrier USS Theodore Roosevelt.
The South Korean military says the three countries enhanced their deterrence and response against North Korean nuclear and missile threats.
It also says the countries completed the drill in bad weather, showing their strong will to develop trilateral security cooperation.
North Korea denounced the exercise, raising speculation that it may use the drill as an excuse to fire ballistic missiles or carry out other forms of provocations.