South Korean forces near the heavily militarised border accidentally launched a fully armed antiaircraft missile yesterday that exploded in mid-air, injuring at least three people.
Defence ministry officials said the missile was fired in the morning during an equipment-checking drill at an air force base in the western port city of Inchon, some 40 km from the border dividing the two Koreas.
The Korean air force later said in a statement that an electrical defect occurred as soldiers turned on a switch which signified that all was ready for inspection.
"Normally the missile cannot be launched with this switch," the statement said.
"A circuitory problem, not human error, was the cause of the accident," it added.
The statement said military authorities would continue to investigate the reason behind the defect.
Air force Lt Col Lee Sung-ryol said earlier that an automatic safety device caused the missile to self-destruct in mid-air three seconds after it was launched because a target was not assigned to it.
The missile was fully armed, he said. Reports earlier had said the missile was unarmed.
Fragments from the exploding missile hit a nearby residential area, injuring at least three civilians and damaging cars and homes, Yonhap Television News (YTN) said. The flaming debris also set off a fire on a nearby hill.
One man was brought to hospital with head injuries from the missile's fragments.
Local television showed images of damaged cars and broken windows from the missile fragments. Police said 41 cars and nine homes and business were reported damaged by the explosion.
Some 165 sq metres of trees and brush were burnt down by flames on the hill, police said.
The missile was identified as a 34-year-old "Nike Hercules" with a target range of some 160 km, designed for shooting down enemy aircraft and large missiles, YTN said. The accident near the last Cold War frontier came as North Korea was escalating its war of words with the US.