The United Nations says three crew members are dead after an Ethiopian military helicopter crashed inside the compound of the UN peacekeeping mission for the disputed Abyei region on the Sudan-South Sudan border.

The statement says 23 passengers were on board when the helicopter crashed on Saturday morning while carrying Ethiopian soldiers. Ten passengers are injured, three in critical condition.

The UN force says the cause of the crash is not immediately known.

Ethiopia is the only troop contributor to the UN mission, with some 4 500 personnel on the ground.