27 Aug 11 – Actually, it was more than 10,000. The earthquake swarm started late Tuesday and continued through Friday. While many went unnoticed by the local population some of the larger tremors, including eight exceeding 3 magnitude were felt in the towns of Chemnitz, Karlovy Vary, Birch, and Luby.
In recent years, scientists have noted an increase in the movement of magma towards the earth’s surface in the Cheb Basin, western Czech Republic. They say rising magma could be one of the causes of the earthquake swarms, which regularly occur in the Vogtland, North-West Bohemia, the Fichtelgebirge and the Upper Palatinate.
Thanks to Caroline Snyder for this link