2009 L'Aquila earthquake region saw dozens of significant aftershocks following the main earthquake. The strongest, which hit at 19:47 CEST on 7 April, measured magnitude 5.3 and caused further damage. According to the Italian National Geophysics Institute director Boschi, the aftershock epicentres migrated south-east, thus lessening the risk of further major shocks near populated areas. Aftershocks caused safety problems for rescue crews searching for injured victims trapped in precarious structures in the historic center of L'Aquila, a medieval city. Using cranes and backhoes to remove loose bricks and broken timbers, the crews were aware that even a small aftershock could have triggered the
April 2011 Fukushima earthquake Fukushima Hamadōri earthquake was succeeded by a number of smaller tremors; that same day, at least 11 earthquakes of magnitude 3.5 M or higher were recorded near its epicentre. Of the series, the strongest registered at a magnitude of 5.5 M and occurred within 3.5 hours after the initial quake. A shallow magnitude 6.0 M (6.4 M) earthquake and several smaller tremors struck the region on 12 April. The earthquake struck in the late afternoon near a moderately populated region of the Fukushima Prefecture, although most structures around the epicentre were resistant to earthquake shaking. Focussed at an unusually shallow