(REUTERS)  A 5.3 magnitude shallow earthquake killed at least four people, including a U.S. tourist, and injured dozens when it rocked a copper-producing region popular with trekkers late on Sunday, authorities said. The quake struck just 8 kilometers (5 miles) deep in the Caylloma province of the Andean region Arequipa and at least five aftershocks shook the region anew on Monday, the Geophysical Institute of Peru said. The USGS reported the earthquake as having […]