BEIJING, Feb. 12 -- President Xi Jinping and Premier Li Keqiang ordered concerted effort to guarantee safety and property after an earthquake hit northwest China's Xinjiang region Wednesday.

President Xi and Premier Li issued instructions on relief work soon after the 7.3-magnitude quake struck at 5:19 p.m.

Local authorities and departments were urged to check disaster situations, conduct emergency management and strengthen seismic monitoring.

The epicenter was at a depth of 12 km in Yutian county in southwest Xinjiang, according to official readings by the China Earthquake Networks Center.

Another 5.7-magnitude quake hit the same area at 5:24 p.m. at a depth of 5 km, followed by more than a dozen quakes under 5-magnitude, the center added.

No immediate casualties or damage have been reported in the sparsely-populated area.