GRINDAVIK, Iceland >> A volcano has erupted in southwestern Iceland, sending a flash of light into the evening sky and spewing semi-molten rock into the air in a spectacular show of the Earth’s power in the land known for fire and ice.

The eruption Monday night appears to have occurred about 4 kilometers (2.5 miles) from the town of Grindavik, the Icelandic Meteorological Office said. The town near Iceland’s main airport was evacuated in November after strong seismic activity damaged homes and raised fears of an imminent eruption.

Iceland, which sits above a volcanic hot spot in the North Atlantic, averages an eruption every four to five years. The most disruptive in recent times was the 2010 eruption of the Eyjafjallajokull volcano, which spewed huge clouds of ash into the atmosphere and led to widespread airspace closures over Europe.

But the eruption on the Reykjanes Peninsula, about 50 kilometers (31 miles) southwest of the capital, Reykjavik, wasn’t expected to release large amounts of ash into the air. Iceland’s foreign minister, Bjarne Benediktsson, tweeted that there were no disruptions of flights to and from the country, and international flight corridors remained open.

Icelandic broadcaster RUV showed a live feed of the eruption on its website. Christmas carols played in the background.

By early Tuesday afternoon, the Icelandic Meteorological Office reported that the size of the volcanic eruption at Sundhnuksgígar “continues to diminish.” It said the lava flow was estimated to be a quarter of what it was at the time of the eruption. Lava “fountains,” which reached as high as 30 meters (yards) have also been falling.

Prime Minister Katrin Jakobsdottir told RUV that for now, the lava was not endangering critical infrastructure near the volcano. Although the lava flow was moving in a promising direction, precautions were nevertheless being taken near the Svartsengi power plant.

“We also know that the flow of lava can change the surrounding landscape, so this can change with short notice,” Jakobsdottir said.

The November evacuation of Grindavik meant few people were near the site of the eruption when it occurred, and authorities have warned others to stay away. The nearby Blue Lagoon geothermal spa — one of Iceland’s biggest tourist attractions — also closed temporarily last month as a swarm of earthquakes put the island nation on alert for a possible volcanic eruption.

Nonetheless, the residents of the evacuated fishing community of 3,400 had mixed emotions as they watched orange flames touch the dark sky. One month after the evacuation, many are still living in temporary accommodations and don’t expect to ever be able to return to live in their homes.

“The town involved might end up under the lava,” said Ael Kermarec, a French tour guide living in Iceland. “It’s amazing to see but, there’s kind of a bittersweet feeling at the moment.”

Yet still they came, anxious to witness the spectacle even if their community may not survive nature’s explosive fury. Grindavik resident Ingibergur Thor Olafarson said it was just amazing. But he was happy it was still far from town.

“(I was) born and raised in Grindavik, so seeing the eruption here I think is the best for our town, because this location is far away,” he said.

Magnus Tumi Gudmundsson, a scientist who flew over the site on Tuesday morning on a coast guard research flight, told RUV that he estimates twice as much lava had already spewed than did during the entire monthlong eruption on the peninsula over the summer.

Gudmundsson said the eruption was expected to continue decreasing in intensity, but that scientists have no idea how long it could last.

“It can be over in a week, or it could take quite a bit longer,” he said.

Helga Torfadottir, a volcanologist at the University of Iceland, said it is too early to know how long the eruption will last, but that it seems somewhat stable for now.

“It’s just in time for Christmas,” she said. “Hopefully it will stay like this, or stop, because this could affect some infrastructure, so hopefully it will not do that.”

Matthew Watson, a professor of volcanoes and climate at the University of Bristol, said that tourists should strictly follow travel advisories because hazards such as new eruptions can quickly put people in harm’s way.

“As is common with this eruptive style, it began with a sustained eruption of ballistics that, over time, has lengthened to form a fire curtain — a long fissure out of which lava is being violently ejected,” he said. “This style of eruption is amongst the most spectacular ever seen, and there will be a strong pull for tourists, even though the Blue Lagoon complex has again shut.”

The spectacular natural phenomenon is already proving hard for people to resist.

“It’s just (like) something from a movie!” said Robert Donald Forrester III, a tourist from the United States.