A South Korean fighter jet crashed in the country's western waters on Wednesday afternoon for an unidentified reason, according to local press reports.

The two-seat KF-16D fighter jet of the South Korean air force crashed into western waters at about 12:13 pm local time (0313 GMT), 13 minutes after taking off for a flight training from an air base in Gunsan, around 270 km south of the capital Seoul.

Two pilots aboard the jet ejected right before the crash, and were in a good condition of health.

It marked the first incident in about 10 months since April last year when a F-15K warplane crashed while coming back to an air base in southeast of South Korea after a flight training.

The exact cause of the accident was not known yet. The air force planned to form a task force to figure out why it happened.