Seoul: South Korea and the United States have conducted missile tests in response to North Korea's weapons tests in recent days.

A South Korean ballistic missile exploded on Wednesday during a live-fire drill with the United States in retaliation for North Korea's missile test.

The explosion and subsequent fire spooked and confused residents of the coastal city of Gangneung, who were already unsettled by increasingly provocative weapons tests by rival North Korea.

Local residents were worried about a North Korean attack as the army and government officials were slow to give an explanation about the explosion.

South Korea's Joint Chiefs of Staff said no injuries were reported in the explosion of a short-range Humu-2 missile that crashed into an air force base on the outskirts of the city.

A Joint Chiefs of Staff official said the missile's warhead did not detonate at the time of the crash and that the fire was caused by burning rocket propellant. Officials said the missile fell shortly after launch and did not affect civilian facilities.

Kwon Seong-dong, a ruling party lawmaker representing Gangneung, wrote on Facebook that a “weapons system operated by our blood-like taxpayer money ended up threatening our own people” and called for the military to thoroughly investigate the missile failure. He also criticized the military for not issuing a notice about the failure while maintaining a media embargo on the joint drills.

"It was an irresponsible response," Kwon wrote. "They don't even have an official press release yet."

South Korea's military acknowledged the malfunction hours after internet users raised alarm about the blast and posted social media videos showing an orange ball of flames emerging from an area they described as near the air force base. It said it was investigating what caused the “abnormal flight” of the missile.

The U.S. and South Korean militaries are conducting joint exercises to show their ability to deter a North Korean attack on the South. During

Tuesday's drills, they conducted bombing runs by F-15 strike jets using precision munitions and launched two missiles each that are part of the Army Tactical Missile System.

Seoul's Joint Chiefs of Staff said the U.S. Aircraft carrier USS Ronald Reagan was scheduled to return to waters east of South Korea on Wednesday to demonstrate the allies'.

The homegrown Hyumoo-2 is key to South Korea's preemptive and retaliatory strike strategies against the North. Some versions of the missile are similar to Russian-designed Iskander missiles, which also inspired a localized variant in North Korea as it expands its arsenal of nuclear-capable short-range weapons designed to evade South Korea's missile defences.

North Korea's successful launch of a nuclear-capable ballistic missile hours before the drills was the country's most provocative weapons demonstration since 2017 and was its fifth round of weapons tests in 10 days.

That missile has a range capable of striking Guam, which is home to one of the largest military facilities maintained by the U.S. in Asia. North Korea 2017 also tested missiles capable of hitting the continental United States.

North Korea has fired nearly 40 ballistic missiles over about 20 different launch events this year, exploiting Russia's war on Ukraine and the resulting deep divide in the U.N. Security Council to accelerate its arms development without risking further sanctions.

The United States, Britain, France, Albania, Norway and Ireland called for an emergency meeting of the U.N. Security Council over the latest North Korean launch. The open meeting was scheduled for 3 p.m. Wednesday.

Washington's nuclear diplomacy with Pyongyang has stalled since 2019 over disagreements in exchanging the release of crippling U.S.-led sanctions against the North and the North's disarmament steps.