The embattled nation, facing 24-hour provocation from its North Korea neighbour and leader Kim Jong-un, carried out live-fire missile drills off the west coast of the Korean Peninsula.

Two AH-64E Apache Guardian choppers each fired a Stinger air-to-air guided missile at target drones 1.5 miles away.

Military officials said it was the first live-fire Stinger missile drill by the country's new Apache unit.

They declared the tests “successful”.

The Stinger missile is a powerful weapon capable of destroying enemy aircraft or unmanned drones infiltrating South Korean airspace at relatively low altitudes.

The US military uses Stingers, known for high accuracy, as a portable air defence system. 

The South Korean Army has modified the weapons for deployment on Apache helicopters which can carry up to four missiles with a maximum range of 3.7 miles.

Last month, the Army held an Apache Hellfire air-to-surface missile exercise in addition to a number of rocket and machine gun live-fire drills.

The Army introduced 36 AH-64E Apache helicopters last year and created two Apache battalions.

Pilot and maintenance crew training has been completed and the units will be put into operation early next year.

Drill commander Lt Col Kim Sang-joon said: “The Apache battalions are the core combat element of the army's aviation force and can strongly retaliate against any type of enemy provocation.”

The military drills come as South Korean President Moon Jae-in began a four-day visit to China.

Relations between China and South Korea have been strained by Seoul’s deployment of a US missile-defence system in response to North Korea’s advances in nuclear and ballistic-missile technology.

But both sides have agreed to set aside the dispute, paving the way for Mr Moon’s first visit to China since taking office in May.

Chinese Foreign Ministry spokesman Lu Kang said: “China and South Korea share common interests and similar positions on denuclearizing the Korean Peninsula through dialogue and negotiation.”