CAVEZZO, Italy (Reuters) - An earthquake killed at least 15 people in northern Italy on Tuesday, damaging buildings and spreading panic among thousands of residents still living in tents after a tremor in the same region destroyed their homes just over a week ago. Officials said several people were trapped under the rubble of houses and warehouses in the Emilia-Romagna region, where several building sites and workshops had just reopened after the previous quake on May 20. Civil protection officials said 15 people were confirmed dead. ...