It was a piece of the glacier Breidamerkurjokull in the outskirts of Jokulsarlonlagunen came off. In the video you see a group escape from the pebbly beach, they are standing on in order to escape the large scales.
According to the AP had the tourists been told by the wizard to immediately leave the pebble beach if something like this would happen. No person was injured in connection with the incident.
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