The magnitude-6.0 quake struck in the middle of the night, about 35km (22 miles) north of the city of Bologna. An aftershock of 5.1 caused more buildings to collapse. The aftershock destroyed a clock tower. The tremor forced many terrified residents into the streets.More than 3,000 people were later evacuated from their homes amid fears of fresh tremors.Northern Italy is frequently rocked by little earthquakes. More information from the BBC here.