Two Air Force training planes collided mid air on while on an exercise, killing all four on board, the South Korean military has said.
Truetells Nigeria reports that the four occupants were ejected from the two aircraft but did not survive.
The two KT-1 planes took off from a military base in the southern city of Sacheon.
On board the planes were soldiers receiving pilot training and an instructor.
The collision occurred a few minutes after take-off. It was initially unclear exactly what preceded the crash.
The KT-1 is a single-engine turboprop aircraft; it is locally made production and has been in service since 2000.
According to South Korean media reports, the two aircraft crashed into a field near Sacheon.
More than 60 rescue workers were deployed.
A fire broke out on the roof of a church after aircraft debris fell onto the building.
However, the fire was quickly extinguished.