The region near the city of Puerto de la Cruz was the worst hit. Ten people were swept into the sea by powerful waves. A woman had a heart attack and died. Attempts to resuscitate her were unsuccessful. The other nine people were taken to a hospital with injuries.
A man was rescued from the water by helicopter near the town of La Guancha, but was pronounced dead on arrival at hospital, officials there said.
A man was also found in poor condition in the water at El Cabezo beach. He also could not be resuscitated.