Among the injured are both civilians and military personnel. For several of them, the situation is reported to be serious.
Thursday's incident occurred in Pocheon, South Korea, a town 25 kilometers south of the demilitarized border with North Korea, reports the South Korean news agency Yonhap.
A church building and parts of several houses were damaged, according to the state rescue service.
The South Korean Air Force confirms that two fighter jets mistakenly dropped four bombs each outside the designated firing range during a military exercise with the USA. This was due to one of the pilots entering incorrect coordinates before the flight.
"We deeply regret the unintentional dropping of the bombs, which resulted in civilian casualties, and wish the injured a speedy recovery," the Air Force says in a statement.
A local resident tells Yonhap that he was at home watching TV when the accident occurred.
I suddenly heard an enormous explosion, like thunder, and the whole house shook. When I went out, everything was chaos, he says.
The South Korean military is investigating the incident and has set up a special committee to take necessary measures, including investigating the compensation issue.