An earthquake measuring 5.2 on the Richter scale jolted Nangchen County in the Tibetan autonomous prefecture of Yushu in northwest China's Qinghai Province at 3:48 p.m Sunday, said the China Earthquake Networks Center.

The epicenter was monitored at 32.4 degrees north latitude and 95.9 degrees east longitude with a depth of 10 km, the center said in a statement on its website.

A fresh 3.1-magnitude quake shook the Nangchen county four minutes after the 5.2-magnitude quake, according to the center.

No casualties have been reported so far, said Wen Guodong, vice secretary of the prefectural committee of the Communist Party of China.

"We felt the quake strongly in Nangchen, but near our office we haven't found any collapsed buildings," said Drimi Lhundrup, deputy chief of the county government.

The county is about 185 kilometers south of Gyegu Town, the seat of the Yushu prefectural government and the epicenter of the 7.1-magnitude earthquake that struck in April 2010.

The quake last year killed nearly 2,700 people in Yushu, a largely Tibetan region with a population of 350,000, and flattened the entire town of Gyegu, leaving more than 100,000 residents homeless.

Post-quake rebuilding began in Yushu on June 20 last year and hundreds of new homes and public facilities have been built. The government's three-year rebuilding plan will cost an estimated 31.65 billion yuan (about 4.86 billion U.S. dollars).