By Soo-hyang Choi

BUSAN, South Korea (Reuters) – South Korean and U.S. troops launched their largest amphibious landing drills in years involving a U.S. amphibious assault ship, officials said on Thursday, a day after North Korea tested four long-range cruise missiles.

The USS Makin Island docked at a naval base in the southeastern port city of Busan on Wednesday to join the Ssangyong exercise, which kicked off on Monday near Pohang on South Korea’s east coast and will last until April 3.

About 12,000 sailors and marines from the two countries will take part, as will 30 warships, 70 aircraft and 50 amphibious assault vehicles, the South Korean military said.

Hours before the ship docked, North Korea fired four cruise missiles off its east coast, South Korea said, in apparent protest of ongoing drills by the U.S. and South Korea.

Captain Tony Chavez, commanding officer of the Makin Island, said the launches were “escalatory,” and that the combined exercises with South Korea are aimed at building “muscle memory” to respond to a crisis if needed.

“It does not matter where that threat is coming from. We are ensuring that we are able to amass forces to maintain maritime and air superiority and defend Northeast Asia or all of the Indo-Pacific region,” Chavez told reporters aboard the ship.

The Makin Island carries 10 F-35 stealth fighters in addition to dozens of armoured vehicles. The ship’s welldeck, which can be flooded to provide direct access to the sea, allows it to launch and recover landing craft and other amphibious vehicles, the U.S. military said.

“Our biggest thing is that we have all the Marines,” said the Makin Island’s public affairs officer, Lieutenant Jarred Reid-Dixon. “We can take people on here and put them on the ground to seize an area if we had to.”

The allies were scheduled to conclude 11 days of their regular springtime exercises, called Freedom Shield 23, on Thursday, though they have other field training exercises continuing under the name Warrior Shield.

Pyongyang has long bristled at exercises conducted by South Korean and U.S. forces, saying they are preparation for an invasion of the North. South Korea and the U.S. say the exercises are purely defensive.

Last week, North Korea fired an intercontinental ballistic missile into the sea between the Korean peninsula and Japan in a “warning to the enemies,” and conducted what it called a nuclear counterattack simulation against the United States and South Korea over the weekend.

(Reporting by Soo-hyang Choi. Editing by Gerry Doyle)

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