An earthquake measuring 5.1 on the Richter scale on Thursday hit China's Wenchuan County, which was the epicentre of the May 12 earthquake last year that left more than 87,000 people dead or missing, an official said.

According to the National Earthquake Network Center, the earthquake took place in Wenchuan County in southwest China's Sichuan Province at 2.23 am on Thursday. No casualties or geological disasters have been reported, said Liao Min, head of Wenchuan County.

The epicentre was located at 31.3 degrees north latitude and 103.3 degrees east longitude. The quake took place about 22 km underground.

A rescue team sent to Shapai Village of Caopo Township, the epicentre, reported telecommunication had been resumed as of 11 am, but power supplies were still cut off.