POCHEON, SOUTH KOREA (REUTERS) – Tanks and howitzers sent smoke and shockwaves through the air less than 32km from the fortified border with North Korea on Wednesday (Aug 31), as more than 1,000 South Korean and US troops held a major live-fire exercise in stepped up practice for war.

South Korea and the United States have resumed the largest field exercises in years after diplomatic efforts and Covid-19 restrictions led to many drills being scaled back.

The allies see the exercises as a key part of their efforts to deter North Korea and its growing nuclear arsenal, but North Korea has called them a rehearsal for war and they have faced criticism even in South Korea and the US.

Reuters was among a handful of media granted rare access to the drills on Wednesday.

They were the first division-level exercises for the 2nd Infantry Division/ROK-US Combined Division, the US military’s only multinational division formed in 2015. ROK are the initials for South Korea’s official name.

The drills included live fire from American and South Korean howitzers, tanks, machine guns and mortars. American A-10 attack aircraft and Apache helicopters also participated.

Rounds from howitzers pounded into a mountainside at the Rodriguez Life Fire Complex, as tanks from both sides manoeuvred and fired their guns at targets, sending shockwaves across the valley and smoke and dust into the air.

Colonel Brandon Anderson, the division’s deputy commander for manoeuvre, said the drills were not aimed at any one adversary, but they obviously took into account the “reason for the US-ROK alliance” – alluding to North Korea.

“We’re all here for a reason, we all know that’s a potential (threat), and how we would defend against it is what we’re trying to demonstrate here,” he said, adding that the drills underscore that U.S. forces won’t be leaving the peninsula.

“We are here for the long haul. As long as there is a threat out there, it gives us purpose, and purpose to train.”

The United States has about 28,500 troops in South Korea.

The drills also form part of the US military’s recent efforts to refocus on large-scale combat operations, and were designed to simulate a counter-attack against a “near-peer” enemy who could match the allies in capabilities, Anderson said.

The conflict in Ukraine had provided lessons on the importance of alliances and the need to improve long-range artillery and surveillance and reconnaissance capabilities, he added.