Photo: The Canadian Press

Ancient columns lie on the ground following an earthquake at the Greek island of Kos on Saturday, July 22.

Hundreds of people on the eastern Greek island of Kos have spent the night sleeping outdoors after a powerful earthquake killed two tourists and injured nearly 500 others across the Aegean Sea region in Greece and Turkey.

Residents and tourists were too afraid to return to their homes and hotels, camping out instead in parks and olive groves, or slumbering in their cars or on lounge chairs.

The most seriously injured in Greece were airlifted to hospitals on the mainland and the southern island of Crete, and at least two were listed in critical condition Saturday.

The U.S. Geological Survey measured the quake, which struck early Friday, as being of magnitude 6.7, with Greek and Turkish estimates a fraction lower. Two men, one from Turkey and one from Sweden, were killed when a collapsing wall smashed into a popular a bar in the Old Town of Kos.

The Turkish man's parents were on the island Saturday making arrangements to repatriate his body.

Panagiotis Bekali, a 30-year-old who has lived on Kos for several years, spent the night sleeping in an olive grove with his entire family. His 5-year-old son and 16-year-old nephew slept in the family car.

"There were cracks in the house (from the earthquake) so we went straight out," he said. "We were afraid to stay indoors so the whole family slept outside."

Dozens of aftershocks have shaken the island, further rattling residents and tourists.

John Grant, a 60-year-old tourist from Britain, said he felt safer sleeping outside.

"I think coming from somewhere that doesn't have earthquakes, you don't understand," he said from his makeshift bed set up on a lounge chair. "So to me it was very frightening being in the building, but being outside I know I'm safe."

About 350 of the injuries occurred in Turkey, in Bodrum and other beach resorts, as people fled buildings and as the sea swell flung cars off the road and pushed boats ashore. Seismologists said the shallow depth of the undersea quake was to blame for the damage.