ROME-According to scientists, a 4.2-magnitude earthquake struck Italy’s Campi Flegrei region west of Naples in the early hours of Wednesday, the largest tremor in the area in 40 years. According to the civil protection office, the quake terrified locals but caused no casualties or damage. The Campi Flegrei (Phlegraean Fields) are a massive volcano that is flat rather than cone shaped. While it is not as well-known as adjacent Vesuvius, a recent spike in activity has shook nerves. The tremor occurred at 3:35 a.m. (0135 GMT) at a depth of around three kilometres (almost two miles) and was felt throughout much of Naples. “It was the largest earthquake in the last 40 years,” said Mauro Di Vito, director of Italy’s National Institute of Geophysics and Volcanology (INGV).