A dozen U.S., South Korean and Japanese military aircraft flew over Japan and South Korea on Wednesday and conducted live-fire bombing runs in a show of force to North Korea.

The exercise involved four U.S. Marine Corps F-35Bs from Marine Corps Air Station Iwakuni, Japan; two U.S. Air Force B-1B Lancer bombers from Andersen Air Force Base, Guam; two Japanese F-15J fighters; and four South Korean F-15K fighters.

"North Korea's actions are a threat to our allies, partners and homeland, and their destabilizing actions will be met accordingly," said Gen. Terrence J. O'Shaughnessy, Pacific Air Forces commander, after an unscheduled visit to Japan to meet with his counterparts. "This complex mission clearly demonstrates our solidarity with our allies and underscores the broadening cooperation to defend against this common regional threat. Our forward-deployed force will be the first to the fight, ready to deliver a lethal response at a moment's notice if our nation calls."

The mission took 10 hours, during which the F-35s, B-1s, and F-15Js flew over the water near Kyushu, Japan. Then, the U.S. aircraft joined the F-15Ks, flew across the Korean Peninsula and conducted live-fire training at the Pilsung Range before heading back home.

Lt. Gen. David Berger, commander of Marine Corps Forces Pacific, said the new F-35s underscored the statement that the allies were showing to North Korea. "The F-35 embodies our commitment to our allies and contributes to the overall security and stability of the Indo-Asia Pacific region," he said in a statement. "By forward-basing the F-35, the most advanced aircraft in the world, here in the Pacific, we are enabling the Marine Corps to respond quickly during a crisis in support of Japan, the Republic of Korea, and all our regional partners."

This week, North Korea fired an intermediate-range ballistic missile that flew over the northern tip of Japan and splashed into the Pacific Ocean about 500 nautical miles east of the country.

President Trump expressed his frustration with North Korea on Wednesday, tweeting that "talking is not the answer!" Asked to respond, Defense Secretary Jim Mattis later said "we are never out of diplomatic solutions," before his meeting with South Korean Defense Minister Song Young-moo.

"We continue to work together, and the minister and I share a responsibility to provide for the protection of our nations, our populations, and our interests, which is what we are here to discuss today," Mattis said.

The following photos were provided by U.S. Pacific Command: