A flood of lava flowed from a crack in the ground in Geldingadalur, near Mount Fagradalsfjall in Iceland, according to video footage shot by a Coast Guard helicopter.
"The eruption started at Fagradalsfjall in Geldingadalur around 8:45 p.m. GMT this (Friday) evening.
The eruption is considered to be small in size, and the crack is about 500-700 meters long.
The lava is less than a square kilometer in size, "the Meteorological Service (IMO), which monitors seismic activity, said in a statement.
"There is little eruptive activity in this area," he added.
The Krysuvik volcanic system, which does not have a main crater, is located south of Mount Fagradalsfjall on the Reykjanes peninsula in southwest Iceland.
The eruption site is about 5 km inland.
"The first notification was received by the Meteorological Agency at 9.40 p.m. GMT. The eruption was confirmed by webcams and satellite images," the agency said on its website.
>> To see: Climate change threatens Iceland's volcanoes and glaciers
The police and the coast guard were dispatched to the scene, but the population was advised not to approach the scene.
The Krysuvik volcanic system has been inactive for 900 years
Icelandic Keflavik International Airport and the small fishing port of Grindavik are only a few kilometers away, but the area is uninhabited and the eruption is expected to be safe.
The authorities did not report an ash fall immediately but fragments of tephra (solidified magma) and gas emissions could occur.
Police recommended residents living east of the volcano to close their windows and stay indoors due to the risk of gas pollution.
Gas emissions from volcanoes, especially sulfur dioxide, can be high in the immediate vicinity of an eruption and can be a health hazard and even fatal.
At a distance, pollution can exceed acceptable limits depending on the winds.
The gas "can cause disturbance and have adverse health effects," the Icelandic Environment Agency warned.
Volcanic eruptions in the region are known as effusive eruptions, where most of the lava flows over the surface of the volcano, unlike explosive eruptions which spew clouds of ash high in the sky.
The Krysuvik volcanic system has been inactive for 900 years, according to the Meteorological Bureau, while the last eruption on the Reykjanes Peninsula dates back almost 800 years, to 1240.
32 active volcanoes in Iceland
The area had been under increased surveillance for several weeks after a magnitude 5.7 earthquake was recorded on February 24 near Mount Keilir, on the outskirts of Reykjavik.
This quake has since been followed by an unusual number of smaller tremors - over 50,000, the highest number since digital recordings began in 1991.
Seismic activity has since moved several kilometers to the southwest, concentrating around Mount Fagradalsfjall, where magma has been detected just one kilometer below the Earth's surface in recent days.
Iceland has 32 volcanoes currently considered active, the highest number in Europe.
The country has experienced an eruption every five years on average.
The vast island near the Arctic Circle straddles the Mid-Atlantic Ridge, a fissure in the ocean floor separating the Eurasian and North American tectonic plates.
The displacement of these plates is partly responsible for the intense volcanic activity of Iceland.
The most recent eruption took place in Holuhraun, starting in August 2014 and ending in February 2015, in the Bardarbunga volcanic system in an uninhabited area in the center of the island.
This eruption did not cause major disturbances outside the immediate vicinity.
But in 2010, an eruption at Eyjafjallajokull volcano sent huge clouds of smoke and ash into the atmosphere, disrupting air traffic for more than a week with the cancellation of more than 100,000 flights worldwide and some 10 million passengers stranded.
With AFP
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