Two aftershocks hit the Greek island of Kos on Saturday night, just a day after a 6.7 magnitude earthquake killed two people and injured nearly 500 others.
The first aftershock, of 4.4 magnitude, hit the island about 8 p.m. local time and was followed 16 minutes later by a 4.6-magnitude tremor, the Athens Geodynamics Institute reported.
The fresh tremors meant more worrying for residents and tourists on the island, as hundreds chose to spend the night sleeping outside, too scared to return to their homes or hotel rooms.
Officials on the island were assessing damage to cultural monuments and infrastructure, such as the port's 14th-century castle and other older buildings affected by the quake.
The island's port was among the damaged structures, along with a minaret from an old mosque.
The port was closed and ferry services were canceled until further inspection. Passengers were rerouted to nearby islands.
Kos Mayor Giorgos Kyritsis said that most of the residential buildings affected were old, predating earthquake building codes.
One that collapsed dated to the 1930s, Kyritsis said. "There are not many old buildings left on Kos. Nearly all the structures on the island have been built under the new codes to withstand earthquakes,'' he added.
Greek authorities said the two tourists killed were from Turkey and Sweden but did not disclose their names.
At least five people were seriously injured and were flown to a hospital on the Greek island of Crete.
The earthquake was the second in the region this year to exceed a magnitude of 6.0, a level that can cause considerable damage.