The eruption started northeast of Sýlingafell before 1pm on Wednesday.There was an intense earthquake in the Sundhnúks crater series since shortly before 11am.Grindavík, the Blue Lagoon and the power plant in Svartsengi were evacuated before noon.The National Police Commissioner, in consultation with the police chief in Suðurnes, has declared a state of emergency due to the eruption.More magma had accumulated under Svartsengi than before the previous eruption.Activity in the eruption had declined significantly by Thursday morning.