Soldiers with the Theater Air Naval Ground Operations, or TANGO, security force fire from cover at the Rodriguez Live Fire Complex in Pocheon, South Korea, June 25, 2025. (Trevares Johnson/Stars and Stripes)
POCHEON, South Korea — With real ammunition crackling overhead and combat vehicles rumbling through rugged terrain, U.S. and South Korean troops joined forces this week for two days of training just 20 miles from the heavily fortified border with North Korea.
The exercise, known as CALFEX — Combined Arms Live Fire Exercise — brought together elements of the South Korean army’s 15th Infantry Division and the U.S. Army’s 2nd Infantry Division, including Korean Augmentation to the United States Army soldiers, or KATUSAs.
KATUSAs are South Korean soldiers integrated into U.S. Army units. The program started in 1950 during the Korean War.
The drills, held Tuesday and Wednesday at the Rodriguez Live Fire Complex, simulated battlefield scenarios designed to test the longtime allies’ mettle and coordination.
“You can issue all the orders you want, but when the rounds are real and the stakes go up, the way our soldiers rely on each other says everything about the alliance,” Capt. Moses Sun, commander of the Theater Air Naval Ground Operations, or TANGO, security force, said the range on Wednesday.
A U.S. soldier surveys the Rodriguez Live Fire Complex from a Bradley fighting vehicle during joint training with South Korean troops, June 25, 2025. (Trevares Johnson/Stars and Stripes)
An AH-64 Apache with the 5th Air Cavalry Squadron, 17th Cavalry Regiment fires rockets during joint training at the Rodriguez Live Fire Complex in Pocheon, South Korea, June 24, 2025. (Trevares Johnson/Stars and Stripes)
A gunman aboard a South Korean K1A1 tank waits for a firing order during joint training at the Rodriguez Live Fire Complex in Pocheon, South Korea, June 25, 2025. (Trevares Johnson/Stars and Stripes)
A U.S. Army AH-64 Apache watches over maneuvering infantry units during joint training at the Rodriguez Live Fire Complex in Pocheon, South Korea, June 25, 2025. (Trevares Johnson/Stars and Stripes)
More than 80 troops from the TANGO unit, based at K-16 Air Base near Seoul, participated, along with personnel from Camp Humphreys, Camp Casey and Osan Air Base. A similar exercise was held in March, part of a broader effort to sharpen readiness amid persistent tension on the peninsula.
This week’s training included breach-and-clear operations, casualty evacuations and fire-suppression tactics, Moses said. U.S. forces employed Stryker combat vehicles, Humvees and tactical support trucks, and AH-64 Apache helicopters.
An A-10 Thunderbolt II from Osan’s 25th Fighter Squadron delivered air support — a rare appearance as the aircraft is being phased out of service in the region.
The event also marked a milestone for Sgt. Yun Mo Koo, who said he served as the first team leader in the history of the KATUSA program. He directed his squad through live-fire lanes, coordinating movements with U.S. troops and air crews.
“It’s one thing to train with blanks,” he said during the exercise Wednesday. “But being confident in a live fire means that everyone needs to trust each other.”
Roughly 28,500 U.S. troops are stationed in South Korea as part of U.S. Forces Korea.
