Four pilots killed as two South Korean air force planes collide in mid-air

Two South Korean air force planes have collided in mid-air and crashed, killing four pilots, Seoul's military has said.

The KT-1 trainer aircrafts crashed on Friday near Sacheon town, about 300 kilometres south of the capital Seoul, according to military authorities.

"Two KT-1 trainer planes at the Sacheon Air Base collided in mid-air while training and crashed," the defence ministry said in a statement.

Two people — a trainer pilot and an instructor — were aboard each of the two KT-1 aircraft. 

All four ejected from the planes but were later found dead, the air force statement said. 

The four victims were identified as two first lieutenants and their instructors, both civilian employees at the air force.

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Cause unknown

The military will "check the exact situation of damage and investigate the cause of the accident," the statement added.

Over 30 firefighters and emergency responders were dispatched to the crash site, the Yonhap news agency reported.

Friday's crash is the latest incident involving South Korea's air force planes this year.

In January, an air force pilot was killed in a F-5 fighter jet crash.

That incident took place shortly after the country grounded its entire fleet of advanced F-35 fighter jets, after one of them was forced to make a dramatic emergency landing after a major systems malfunction.

The Korean Peninsula remains in a technical state of war, as the armistice that ended the conflict in 1953 has yet to be replaced with a peace treaty.

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