KOS, Greece — Crews of experts began examining the damage to cultural monuments and infrastructure on the eastern Greek island of Kos on Saturday, a day after a powerful earthquake killed two tourists and injured nearly 500 others in the Aegean Sea region that stretches to Turkey’s sprawling coast.

Residents and tourists were still jittery as a series of aftershocks Saturday night continued to rock the island. A tremor measuring a preliminary 4.4 magnitude struck at 8:09 p.m.  (1709 GMT) Saturday, sending residents and restaurant customers scurrying toward the middle of the town’s main square, as far away as possible from buildings.