Moscow: A Russian military jet crashed during a training flight in the Caucasus region of North Ossetia, killing two people on board, the defence ministry said Tuesday.

A statement said the Sukhoi-34 jet crashed "in a mountainous zone" and added that there was "no damage on the ground". It did not specify when the accident happened.

It said a technical problem appeared to have caused the crash, adding that an investigation had been launched to ascertain the reason behind the accident.

North Ossetia, which borders ex-Soviet Georgia, is about 800 kilometres from the front line in Ukraine.

"In the Republic of North Ossetia-Alania, in a mountainous area, an Su-34 aircraft of the Russian Aerospace Forces crashed during a scheduled training flight," Russia's RIA state news agency cited the defence ministry as saying.

"The plane crashed in a deserted area. There is no destruction on the ground. The crew was killed."

The Sukhoi Su-34 is a Soviet-origin Russian all-weather supersonic medium-range fighter-bomber aircraft.