KUNMING -- Relief work has been launched after a magnitude 5.1 earthquake hit Yangbi county in Southwest China's Yunnan province at 7:55 am Monday.

No casualties have been reported so far.

The provincial civil affairs department has dispatched a work team to assist with quake relief work and allocated 500 tents, 1,000 folding beds, 1,000 quilts and 1,000 coats to the quake-hit region.

The epicenter, at depth of about 12 km, was monitored at 25.89 degrees north latitude and 99.8 degrees east longitude, according to the China Earthquake Networks Center.

Four tremors measuring 3 to 4.7 on the Richter scale hit the same region before and after the magnitude 5.1 quake, the center said.

Wang Caixun, a Yangbi publicity official, said the epicenter was at Ajia and Puping villages, where some houses were reportedly damaged.

"Firefighters and medical teams are heading to the villages," Wang said.

As of 9 a.m., a number of houses in nine villages in Yangbi were severely damaged in the quake.

Further investigation is underway.

The provincial surveying, mapping and geo-information bureau has sent five personnel with three drones to take aerial images of the quake-hit areas.