During the night and into the morning of 18. December 2023 an earthquake swarm took place in Tjörnes Fracture Zone just south east of Grímsey island. Largest earthquake in this swarm had a magnitude of Mw3,4 at 08:06 UTC and was felt in Húsavík, Akureyri and Grímsey according to the news. Other earthquakes in this swarm where smaller in magnitude.
Earthquake activity in this area is common and larger earthquakes are frequent. Earthquake swarms happen regularly. This earthquake swarm seems to have ended.