ANKARA, Turkey (AP) — An army helicopter crashed in eastern Turkey on Thursday, killing 10 military personnel on board and injuring three others, the Defense Ministry said. News reports said a high-ranking officer was among the victims.

The Cougar type helicopter crashed near the village of Cekmece, close to the town of Tatvan, in the predominantly Kurdish-populated Bitlis province. It was on its way to Tatvan from the nearby province of Bingol when authorities lost contact with it at 2:25 pm , the ministry said.

The victims included Lt. Gen. Osman Erbas, an army corps commander, said Devlet Bahceli, the leader of Turkey’s main nationalist party, on Twitter. Pro-government Daily Sabah also reported that Erbas was killed. Nine of the victims died at the crash site, while the tenth died of his injuries in hospital, officials said.

The ministry described the crash as an accident, but it wasn’t immediately known what caused it. HaberTurk television said the chopper is believed to have crashed in adverse weather conditions, including snow and fog.

Turkish Defense Minister Hulusi Akar departed for Tatvan together with the country’s chief of military staff and land forces’ commander to inspect the area, the ministry said.