REYKJAVIK — A volcano in southwestern Iceland erupted Wednesday for the fifth time since December, spewing massive lava flows that threaten to cut off the town of Grindavík and prompting the evacuation of the world-famous Blue Lagoon.

Dramatic video and images from the scene showed fountains of red-hot lava shooting into the air along a 3.4-kilometer (two-mile) fissure near Mount Hagafell on the Reykjanes Peninsula.

Iceland’s Meteorological Office said in a statement that “the first estimate of scientists is that the start of this eruption is more vigorous than in previous eruptions in the area.”

The eruption began around 1 p.m. local time on Wednesday following an earthquake at the Sundhnúks crater, Iceland’s public broadcaster RUV reported. The Met Office had earlier warned that a volcanic eruption was likely following “intense seismic activity” at the crater and a build-up of magma in its underground reservoir.

Lava flows have cut off two out of three roads leading to the fishing town of Grindavík, and were steadily moving along a defensive barrier built to save the town and key infrastructure from being destroyed, according to the Met Office.

“Lava is flowing outside the defense walls at Grindavík in several places, and lava is also starting to flow outside the walls at Svartsengi,” Víðir Reynisson from Iceland’s Civil Defense told RUV.

He warned that Grindavík is at risk of becoming completely cut off, though he added that the defense barriers were holding.

“The houses in the west and farthest part of the town would have gone under the lava if it weren’t for the defensive walls, but they are still standing and defending,” Reynisson reportedly said.

Grindavík, a town of about 3,000 people, was mostly evacuated before a previous eruption in December. Residents and responders who remain in the town have been urged to leave while they still can, though police told RUV that three residents are refusing to evacuate.

Electricity to Grindavík was cut on Wednesday as a protective measure as lava flows closed in on high-voltage lines and hot and cold pipes in the ground, Kristinn Harðarsonar, production manager at energy company HS Orka, told RUV.

“Most of the high-voltage lines are gone, the pylons are badly damaged and some are on fire,” the Civil Defense’s Reynisson later said.

Benedikt Ófeigsson from Iceland’s Met Office told RUV that the beginning of this eruption was more powerful than previously due to more accumulated magma in the chamber.

“It’s a lot more lava flow than we’ve seen before,” he reportedly said. “This is reflected in today’s massive lava flows.”

Iceland’s Ministry of Foreign Affairs said in a post on X that there was no disruption to international or domestic flights.

But for the third time in just over two months, the country’s famous geothermal spa and tourist hotspot the Blue Lagoon was evacuated, according to its operations manager.

Just under an hour’s drive from Iceland’s capital and largest city Reykjavik, the Blue Lagoon is one of the country’s most popular tourist attractions. The site is part of southwest Iceland’s Reykjanes Peninsula — a thick finger of land pointing west into the North Atlantic Ocean from Reykjavik.

Iceland is one of the most active volcanic areas on the planet. Rather than having a central volcano, the Reykjanes Peninsula is dominated by a rift valley, with lava fields and cones. — CNN