A military helicopter exploded and crashed Monday on the outskirts of the Cambodian capital of Phnom Penh, killing five trainee soldiers on board and severely injuring one.

The plane, suspected to be a Chinese-made Zhi-9, which can carry up to nine passengers, was carrying soldiers during a training session and was found in a ditch in Dagkor district, about 6 miles from Phnom Penh, according to reports, which said that rescue teams and police officials had reached the site. The plane was one of 12 choppers Cambodia reportedly bought last year from China.

“We are investigating to find out the cause of the crash,” Defense Minister Tea Banh, told Agence France-Presse.

The latest incident follows a similar one in 2008 when Hok Lundy, head of the country's police force, was killed along with the deputy army commander and two pilots when their plane crashed in bad weather.

Chhay Bunna, the chief of Cambodia's police, told Associated Press that the soldiers who died Monday were training to be pilots at the time, and that the aircraft sank into wet mud after crashing in a region filled with rice fields.