South Korea’s air force has apologised after one of its fighter jets accidentally dropped eight bombs in the wrong place during a training exercise on Thursday, injuring 15 civilians and damaging several buildings.

“Eight MK-82 general purpose bombs were abnormally released from an air force KF-16 aircraft, landing outside the designated firing range,” the air force said, adding that the bombs weighed about 225kg each.

“We deeply regret the unintended release of the bombs, which resulted in civilian casualties, and wish those injured a swift recovery,” the air force said in a statement.

The incident occurred at about 10am local time (0100 GMT) in the village of Nogok-ri, part of the city of Pocheon, 16 miles (25km) from the heavily armed border with North Korea.

As the air force announced an investigation, South Korean media reported that the bombs had been dropped in error after a pilot inputted incorrect coordinates.

The incident occurred during preliminary live-fire exercises involving the air force and army in preparation for joint South Korea-US military exercises known as Freedom Shield that are scheduled to run from 10-20 March. The drills are intended to prepare the allies for any potential conflict with the North, which views them as a preparation for an invasion.

The live-fire exercises were suspended while military authorities tried to establish the cause of the incident.

Pocheon’s disaster response centre said six civilians, including two people from Thailand and Myanmar, had been injured and were being treated at hospitals. Several other civilians reportedly suffered feelings of anxiety.

Some of the victims sustained fractures to their necks and shoulders, according to News1. None of the injuries are thought to be life-threatening.

Local people have long complained about the noise and disruption, as well as the potential danger posed by military exercises.

One man, who gave only his surname, Park, told Yonhap news agency he had been at home watching television when the accident happened.

“I suddenly heard an enormous explosion, like a thunderclap, and the whole house shook. When I went outside, everything was in chaos,” Park said.

Cheon Man-ho, 68, who lives about 20 metres from where one of the bombs fell, said he initially thought war had broken out.

“The roof collapsed, windows shattered, and trees were all broken,” Cheon told the Chosun Ilbo newspaper. “When I went to see what was happening, everything was destroyed and black smoke was rising.”

Lee Poong-seop, 65, who has run a car business in the village for 30 years, described the moment of impact. “I was cleaning the car centre when suddenly there was a ‘boom’ sound and the building shook violently,” he told News1. “I’ve lived here my whole life but never heard such a loud sound.”

The military cordoned off the area to check for unexploded bombs, prompting an evacuation order, but later confirmed all eight bombs had detonated.

Media photographs from the scene showed shattered windows and a church building strewn with debris. Local media reported that five homes, a warehouse, a greenhouse and a 1-tonne truck were also damaged.

The air force said it had established an accident response committee to investigate the incident and would “take all necessary measures, including compensation for damages”.

The national fire agency said the bombs were “presumed to have fallen on a village during a South Korea-US joint exercise”. This resulted “in many displaced residents”, it added.

People at a centre for senior citizens felt the impact, even though it is located about 1km from the scene.

“A sudden explosion shook the building. The windows shattered, and one of our teachers was injured and taken to the hospital,” the centre’s director, surnamed Yu, told Yonhap. “Fortunately, none of the seniors were hurt, but they were so frightened that we sent them all home.”

North and South Korea remain technically at war since their 1950-3 conflict ended in an armistice but not a peace treaty.