Lava in Iceland is approaching Grindavik in a new eruption

A state of emergency has been declared in southern Iceland due to another volcanic eruption on the Reykjanes Peninsula, the fourth since December.

This is believed to be the strongest eruption to date. Local media said that the lava reached the eastern defenses surrounding the evacuated town of Grindavik.

People were also transported from the nearby Blue Lagoon, one of Iceland's most popular tourist attractions.

Iceland's airspace remains open. Giant lava spill billowing smoke.

According to the country's Civil Defense Service, the eruption began after 20:00 local time (20:00 GMT) on Saturday between Hagafell and Stora Skogfell – north of Grindavik.

This is a similar location to the eruption that began on December 8.

Footage of the explosion showed clouds of smoke and glowing magma bleeding and boiling from holes in the ground.

Keflavik International Airport and other regional airports were not affected by the explosion.

Geophysicist Magnus Tommy Gudmundsson, who was among those who flew over the affected areas by helicopter, told local media that Saturday's eruption was the strongest yet.

There were two lava streams moving west and south. Local media reported that the lava emanating from the latter reached the eastern defensive walls of Grindavik.

It is also possible for lava to flow into the sea, but this may not happen if volcanic activity declines, Gudmundsson said.

Dangerous gases and small explosions could occur if lava comes into contact with seawater, Einar Besse Gestsson, a natural disaster expert at the Norwegian Meteorological Agency, told Iceland's public broadcaster RUV.

Meanwhile, lava moving west is said to have reached the Grindavikurveg road to Grindavik – heading in the direction of the Blue Lagoon and the Svartsengi geothermal power plant, which supplies hot water to most of the Reykjanes Peninsula.

The Icelandic Meteorological Office said this lava layer was “much wider” than in February, when a previous eruption caused lava to flow in a similar direction.

Ricky Pedersen, head of the Reykjavik-based Nordic Volcanology Centre, told Reuters that several protective dams had been built around them.

There are fears that the fiber optic cables on the road may be damaged, which could lead to interruption of telephone and Internet services.

The Blue Lagoon is closed until further notice as a precaution. Pedersen said there were between 500 and 600 people in the area when the eruption occurred on Saturday.

Between five and ten houses were also disinfected in Grindavik.

The town's roughly 4,000 residents were not allowed to return to their homes until about a month ago after a volcanic eruption in January sent lava spreading into the town, destroying three homes.

Most of them have chosen not to return.

Iceland has 33 active volcanic systems and is located above what is known as the Mid-Atlantic Ridge, the boundary between two of the largest tectonic plates on the planet.

The last time the Reykjanes Peninsula experienced a period of volcanic activity was 800 years ago, and eruptions have continued for decades.

This is now the seventh eruption since 2021, and scientists believe the region is entering a new volcanic era that may last decades or even centuries.