No ash detected, but authorities raise warning to the highest level and close airspace to 18,000 feet

A road closed near the Bardarbunga volcano Photograph: Vilhelm Gunnarsson/Fretabladid/EPA
Authorities have raised the warning code for aviation to red following a volcanic eruption near Iceland’s Dyngjujokull glacier, but no volcanic ash has been detected, Iceland’s authorities said.
There has been heightened seismic activity in the area for about a week. Red – the highest level – indicates that an eruption is imminent or under way, with a significant emission of ash likely.
“The Icelandic Met Office has raised the aviation colourcode over the eruption site to red and the Icelandic Air Traffic Control has closed down the airspace from the earth up to 18,000 feet,” Iceland’s National Crisis Coordination Centre said.
“No volcanic ash has been detected with the radar system at the moment ... Seismic eruption tremor is low indicating effusive eruption without significant explosive activity.”
Ash from the eruption of Iceland’s Eyjafjallajokull volcano in 2010 shut down much of Europe’s airspace for six days.