Provincial seismological officials also reported a series of aftershocks from the earthquake, which struck the province's northeastern city of Xuanwei on Tuesday, measuring 5.1 on the Richter scale, Xinhua news agency said.
"The province will expand relief efforts and closely monitor the situation to accurately predict aftershocks. Four aftershocks have already been recorded in the Xuanwei area," Xinhua quoted the provincial Deputy Governor Niu Shaoyao as saying.
Two students in a village outside Xuanwei were injured trying evacuate their classrooms during the tremor, Xinhua said. No other casualties have been reported.
The death toll from a pair of stronger quakes two weeks ago in the same province has also been raised to five, state media reported on Wednesday.
At least 1,500 were injured and 23,600 left homeless by the November 19 tremors that shook Ninglang county, roughly 250 km (150 miles) west of Xuanwei.
China has appealed for international and domestic aid for shelter victims made homeless by the Ninglang earthquakes, the stronger of which registered 6.2 on the Richter scale.
The affected area is mostly rural and extremely poor.
Temperatures in the mountainous region have dropped to near freezing.
- Reuters - Thomson Reuters Foundation
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