Even now there are occasional aftershocks.
Technically, that strong shaking was an aftershock of the devastating 9 .0 temblor that hit the nation nearly a month ago.
Initial reports say the aftershock caused more deaths and injuries, and led to further damage to homes, buildings, and roads.
In a nutshell, Aftershock argues that a succession of bubbles have set the country on the path to ruin.
State media showed people camping on the streets and in city squares after the government - issued aftershock warning.
The aftershock, centered near the devastated city of Mianyang, was felt across the country.
Japan was rattled by a strong aftershock and tsunami warning Thursday night nearly a month after a devastating earthquake and tsunami flattened the northeastern coast.
There's a significant probability of having an aftershock in the magnitude 7 range, which could be potentially destructive, says Dr. Benz.
A store keeper in Mianyang City, south of Qingchuan, said his store creaked in the aftershock and everyone fled.
If aftershocks can occur years after the fact, how do scientists distinguish an aftershock from a "new" earthquake?