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The eruption is presently not thought to constitute immediate danger. The Civil Protection Agency has however extended road restrictions around the area, anticipating an increased flow of traffic because of the eruption.
The Icelandic Met Office has earlier issued a red alert for aviation over the eruption area. That means that airtraffic is restricted in a large area around the eruption.
Lava is running from the fissure to the southeast. So far volcanic ash production is thought to be minimal. Scientists monitor the situation from a safe distance and will soon fly over the eruption area with the Icelandic Coast Guard's TF-SIF aircraft.
Björn Oddsson, geologist with the Civil Protection Agency, says that so far the eruption is "small and innocent". There is continuing seismic activity in Bardarbunga and Oddsson says the situation will be closely monitored.
The fissure lies in a SW - NE direction, in the northern part of the Holuhraun lavafield, north of Dyngjujokull and south of the Askja caldera. The fissure seems to be located near a row of old craters within the lava field. Holuhraun was formed in an effusive lava eruption in 1797.
The fissure was initially thought to be 100 metres long, but scientists at the location have reevaluated their measurements and now believe the fissure is about 1 kilometer long. Ash is falling near the fissure and explosive activity is minimal, according to eyewitnesses.
The fissure opened up in the same location where a magma intrusion has been propagating away from the Bardarbunga volcano towards the south. The eruption is about 9 kilometres north of Dyngjujokull. Intense seismic activity has been associated with the intrusion in recent days as it as migrated away from Bardarbunga.
This story, by the Icelandic National Broadcasting Service (RUV), was updated on August 29. 2014, at 09:05 GMT.
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