The plane crashed in a mountainous area near the southeastern city of Pohang just before 2:00 pm (0500 GMT) around six minutes after take off, according to the country's navy.

The maritime patrol aircraft was conducting take off and landing training when it crashed for reasons that remain unclear, they said.

"Of the four crew members on board, two bodies have been found and are being prepared for recovery," it said.

A search for the two remaining crew members is ongoing, the navy said. No civilian casualties have been confirmed.

The cause of the incident is currently being investigated, they said.

Fire authorities have dispatched some 40 personnel in response, according to South Korea's Yonhap news agency.

South Korea suffered the worst aviation disaster on its soil in December when a Jeju Air Boeing 737-800 crash landed and exploded into a fireball after slamming into a concrete barrier.