An earthquake of magnitude 4.8 shook southwest China's Sichuan province on Sunday, the US Geological Survey said. No casualties were immediately reported after the temblor rattled Pingwu county of the city of Mianyang in Sichuan, China's state seismological bureau said. The bureau said the quake was an aftershock connected to the massive 7.9-magnitude earthquake that struck Sichuan in May, killing more than 69,000 people and leaving 18,000 missing and presumed dead. A duty officer at the bureau who refused to be named said it is normal for aftershocks to be registered even six months after an earthquake.