A strong overnight earthquake shook a sparsely populated area in western China early Saturday and forced the suspension of high-speed rail service because of tunnel damage, authorities said.

Four people with minor injuries in Menyuan Hui Autonomous County had been treated and released, they said at a news conference.

The magnitude 6.9 quake struck at 1:45 a.M. In a mountainous part of Qinghai province that is 3,659 meters (12,000 feet) above sea level. It was felt 140 kilometers (85 miles) southeast in Xining, the provincial capital, where some people rushed outside of homes and buildings.

Nighttime video posted online by CGTN, the overseas arm of state broadcaster CCTV, showed furniture and ceiling lamps swaying and livestock suddenly standing up and moving in its pen. Photos from the state-owned China News Service showed scattered damage to homes including a broken window and wall tiles and a large ceiling section that had fallen.

There are five villages within 5 kilometers (3 miles) of the epicenter, the official Xinhua News Agency said.

Service on some sections of a high-speed rail line from Lanzhou in Gansu province to the Xinjiang region was halted because of damage to several tunnels, Xinhua said. Some lines between Qinghai and Tibet were closed and inspectors were sent to check the tracks.

Rescue and firefighting teams in Qinghai and neighbouring Gansu province have sent about 500 rescuers to the epicenter, the Chinese Ministry of Emergency Management said in an online statement. Another 2,260 rescuers from neighboring provinces were on standby.

The ministry and the China Earthquake Administration dispatched a team to Qinghai to help investigate the situation and resettle any affected residents.