BEIJING -- (UPDATE) The death toll from a strong aftershock in southwestern China rose to six on Monday, with four more deaths reported, state-run media said.

The four newly reported deaths from Sunday's aftershock came in the city of Hanzhong in northwestern China's Shaanxi province, Xinhua news agency said.

Another 20 people were injured there, Hanzhong major Hu Runze said, adding to hundreds of injured already reported elsewhere.

The aftershock also destroyed 70,000 homes and rattled millions still reeling from the massive earthquake two weeks ago.

The aftershock was centered in quake-ravaged Sichuan province and had a magnitude of 6.4 on the Richter scale, an official with the Sichuan Earthquake Bureau told Agence France-Presse.

It was the strongest of thousands of aftershocks in the region since an 8.0-magnitude quake on May 12 left about 86,000 people dead or missing, the official said.

The US Geological Survey, however, put the quake magnitude at 5.8.

The four deaths add to two reported previously, including one death in Sichuan's Guangyuan city, Xinhua reported a local official as saying.

The official had also said 262 were injured in Guangyuan.

Longnan city in northwest China's Gansu Province also reported one person killed by stones falling from a mountain, and 109 injuries, 15 of them serious.

In Qingchuan County, the epicenter of the aftershock, about 359 people were reported injured, Xinhua said.

The quake sent people fleeing from buildings across southwestern China and was felt as far away as the capital Beijing.