Strong earthquakes shook western and eastern Indonesia on Sunday, sending panicked residents fleeing from their homes. One of the tremors shook telephone and electricity poles and forced the evacuation of a hospital. A 6.1-magnitude earthquake struck waters off Sumatra island early Sunday and was followed 13 hours later by a quake with a preliminary strength of 6.7 on Sumbawa island, to the west, the US Geological Survey said. There were no immediate reports of injuries. The morning temblor rattled residents in Bengkulu, a coastal town 175 kilometers (110 miles) from its center. The region has been hit by a series of strong earthquakes and aftershocks in recent months, putting many on edge.