Article published on the 2008-05-16 Latest update 2008-05-17 11:36 TU
The aftershock hit Lixian county, less than 50 km from the site of the original quake. It measured 5.9 on the Richter scale, while Monday's seism had a magnitude of 7.9, China's state news agency Xinhua reported.
Roads in the already remote region were buried, making access even more difficult.
Mobile telecommunications networks, which had been restored after the earthquake, were knocked out a second time, further complicating rescue coordination, Xinhua reported.
There have been some 122 aftershocks rating above four since Monday, according to Chinese seismologists.
The Chinese government has confirmed 21,000 deaths but estimates that the total could run to more than 50,000.
Meanwhile in Yinghua, rescue workers are racing against the clock to free people trapped in the ruins of factories before they die. Families are forced to make difficult decisions regarding whether to attempt emergency amputations to free loved ones.