Footage posted on social media showed people running in panic as a large section of the cliff peeled off and crashed down close to several bathers. The other six people injured included two children and according to a hospital official they received treatment for minor injuries. O'Connell estimates there are around 400 to 500 people in the area when the rockfall occurred and around a dozen tourist boats were out in the bay.
"There was a rumble and a rock fell, followed by a larger rock and then another".
The rock's weight drove waves on to the crowded beach, Mr O'Connell said, as families scrambled to safety.
The water hit his feet with such a strong force, it knocked him onto his back and went on to cover more than half the beach. Meanwhile, some boats were capsizing in the strong waves. Greek authorities say a landslide at a popular beach on the western island of Zakynthos has resulted in at least one injury, while coast guard officials were seeking to determine whether there were any people missing. The fire department said it had sent 18 rescuers accompanied by a sniffer dog, while a further nine-person crew was heading to the site by helicopter.
Imagine the worst beach trip you possibly can. It is surrounded by steep cliffs and can only be reached by boat but thousands of tourists each year make the journey to visit it.
British woman Wendy Thorpe said she was on a boat with her daughter when the cliff collapsed and there was an "almighty crash".