A US military helicopter taking part in a joint South Korea-US drill has crashed near the North Korean border.

The aircraft was carrying three crew and 13 other personnel during a training exercise, 6 of those are reportedly being treated in hospital for non-life threatening injuries.

A US official described the crash as a "hard landing" in Cheolwon county which is on the border with North Korea.

The Korean peninsula is currently at a state of heightened military tensions, partly due to North Korea's anger over the ongoing South Korea-US military exercises, which it sees as an invasion rehearsal.

There are 28,500 US military personnel permanently stationed in South Korea.