Update 4pm: An Irish woman caught up in a powerful earthquake that struck the Aegean sea says it wouldn't put her off going back.
Two people were killed and hundreds injured on the Greek Island of Kos, while dozens more were injured in neighbouring Turkey.
The Irish embassy is not advising against travel to the region, but people should contact their tour provider before flying out.
Kyna (PR Keena) Rushe is on holiday in Kuakas and says people are trying to go on as normal.
"I think most people are trying to go about their business and keep some form of normality.
"Earthquakes are regular here, probably not to that degree, but it wouldn't put me off returning."
Update 1pm: British and Irish holidaymakers are facing travel disruption at the busiest time of the year after a powerful earthquake off the Greek islands and Turkey killed two people.
Two men, from Sweden and Turkey, died on the Greek island of Kos, while around 200 other people were injured in the quake which also caused cracks to walls and flooding in some buildings in the Turkish resort of Bodrum.
Tourists had to flee their hotel rooms when the tremor, said to have been up to a magnitude of 6.7, struck at around 1.30am, and was followed by aftershocks throughout the night.
There have been no reports of any injuries to British or Irish holidaymakers but some tourists spoke of their shock after experiencing the earthquake.
Lauren Duffy, 20, from Liverpool, said glass and broken pieces of marble statues were among the debris strewn near her hotel, a short drive from Kos’s Old Town.
The University of Chester student said: "We were woken up by really aggressive shaking. We didn’t know what it was. You couldn’t find your balance. It was just a scary situation."
Naomi Ruddock, who is on holiday in Kos with her mother Eleanor, said a staff member told her it was the worst earthquake the area had seen.
The 22-year-old, from London, said: "We were asleep and we just felt the room shaking. The room moved. Literally everything was moving. And it kind of felt like you were on a boat and it was swaying really fast from side to side, you felt seasick."
The quake came as millions of British and Irish holidaymakers are expected to head overseas for their summer holidays and air traffic controllers are dealing with the busiest day in UK aviation history.
Abta said Kos Airport has reopened, but warned of delays, and advised visitors to the affected areas to follow the advice of their travel provider, local authorities and the Foreign Office.
A statement from the travel trade organisation said: "Customers imminently due to travel to this region will be contacted by their tour operator, should it be necessary to discuss changes to their holiday arrangements."
The British Government’s latest guidance for travellers to Greece warns: "Flights and ferry services are being significantly disrupted as a result of the earthquake. Please contact your airline, ferry company or tour operator for updates to services."
Travellers to Turkey are being advised: "There may be disruption to ferry and flight services as a result of the earthquake."
Update 8:04am It is not believed any Irish people have been caught up in a powerful earthquake that killed two people and injured 120 on the Greek Island of Kos.
However, the Department of Foreign Affairs has said it is monitoring the situation.
The 6.7 magnitude quake struck last night while people were sleeping, causing several buildings to collapse.
Hannah Wright is there with her family, including her two young children, they had to temporarily evacuate their hotel.
"There were some quite heavy after shocks and I believe people did come back outside," she said
"There’s probably been in our area a good 100 to 120 people that slept outside on sun loungers."
Earlier:A powerful earthquake struck Greek islands early on Friday morning, damaging buildings and a port, killing at least two people and causing more than 100 injuries.
The island of Kos was nearest to the epicentre and appeared to be the worst-hit, with two deaths and structural damage to older buildings.
Minor damage - cracks in buildings, smashed windows and wrecked shops - appeared widespread, according to city officials.
"The rest of the island has no problem. It’s only the main town that has a problem," Kos Mayor Giorgos Kyritsis told state-run Greek media.
"The buildings affected were mostly old, and were built before the earthquake building codes were introduced."
Rescuers were checking for trapped people inside houses after the quake struck in the middle of the night.
Mr Kyritsis said the army was mobilised along with emergency services. The island’s port was among structures that sustained damaged and a ferry en route there was not docking, the coast guard said.
Giorgos Halkidios, Kos regional government official, said the number of injured was more than 100.
"Two or three of them are in serious condition and are in surgery," he said.
He said the injured included people who were underneath a building that collapsed. Ferry services were suspended due to damage at Kos’s main port, where a 14th-century fortress also was damaged. A minaret from an old mosque also was damaged.
Greek officials said the quake was 6.5-magnitude. It was centred six miles south of Bodrum, Turkey, and 10 miles east-northeast of Kos with a depth of six miles, according to the US Geological Survey.
Turkish disaster officials said the earthquake had a magnitude of 6.3, and more than 20 aftershocks have been recorded.
Esengul Civelek, governor of Mugla province, said there were no casualties according to initial assessments. She said "there were minor injuries due to fear and panic".
In Bitez, a resort town about four miles west of Bodrum, the quake sent frightened residents running into the streets.
Hotel guests briefly returned to their rooms to pick up their belongings but chose to spend the rest of the night outside, with some using sheets and cushions borrowed from nearby lounge chairs to build makeshift beds.
Greece and Turkey lie in an especially earthquake-prone zone.
The authorities later said the number of people injured in the earthquake had risen to more than 120.
Several tourists were stranded outside their hotel after the quake sent them streaming onto Lambi Beach on Kos Island.
Lauren Duffy, a 20-year-old student from Merseyside, was evacuated along with her mother and sister from the Atlantis Hotel, which was strewn with shattered glass.
She said: "We were asleep in our hotel room when we were woken by really violent shaking, and we all were screaming and told to evacuate from the hotel."
She said they were able to return to the hotel just long enough to retrieve their passports before they were forced out again by tremors.
Ms Duffy said no-one was hurt but the broken glass made the area unsafe. She said most of the stranded tourists there are Dutch, Russian and German.