KUNMING - A 4.2-magnitude earthquake jolted a border area near Yongsheng county and Ninglang Yi autonomous county in southwest China's Yunnan province at 5:43 a.m. Friday, according to the China Earthquake Networks Center.

The quake was strongly felt in Yongsheng, where it damaged about 15,000 houses, affecting the lives of more than 13,500 people, according to the county's publicity department.

No casualties have been reported so far, the department said.

The earthquake came shortly after a string of tremors that have hit the province over the past few days.

On Wednesday afternoon, a 4.8-magnitude earthquake jolted Mojiang Hani autonomous county, damaging nearly 1,000 houses and affecting the lives of more than 5,000 local residents.

Prior to that, a 4.9-magnitude quake that occurred at 10:46 a.m. Tuesday toppled 72 houses and damaged 949 others in Qiaojia county. Eight people were injured, including two people who are in serious condition.

Zhang Jianguo, a researcher with Yunnan's seismic bureau, said the earthquakes are not sufficient proof to indicate active crustal deformation in the region.

The earthquakes are not necessarily linked to the drought that has plagued most parts of Yunnan over the past four years, Zhang said.