A 5.7-magnitude aftershock struck Ningqiang County of northwest China's Shaanxi Province Tuesday afternoon.
The aftershock hit the county at about 4:37 PM and the China National Seismic Network located the epicenter at 32.8 north latitude and 105.6 east longitude.
It was strongly felt in the provincial capital of Xi'an and parts of neighboring Gansu Province.
A 5.4-magnitude aftershock had just hit Qingchuan County, which is very close to Ningqiang, in neighboring Sichuan Province at about 4:03 p.m.
Thousands of aftershocks have been reported in Sichuan after the 8.0-magnitude earthquake hit the province's Wenchuan County on May 12.
(Xinhua News Agency May 27, 2008)