By AP/KWMU
WEST SALEM, Ill. – The U.S. Geological Survey says it has recorded the strongest aftershock so far from Friday's earthquake.
Geologists say the tremor just before 12:40 a.m. registered at 4.5 on the Richter scale. Its epicenter was near that of the original quake, about five miles northwest of Mount Carmel, Ill. Friday's quake measured 5.2.
The Monday morning aftershock was at least the 15th. Twelve were reported Friday and Saturday.