In pictures: The Iceland volcanic eruption and the aftermath

A volcanic eruption in southwest Iceland spewed lava and smoke more than 100 metres into the air, creating stark contrast against the sky and snow. Here are some of the most eye-catching images.

Some 100 to 200 cubic metres of lava emerged per second after the eruption, Iceland's Met Office said. Source: AAP / Anton Brink / EPA

Late on 18 December, a volcano erupted in southwest Iceland, spewing lava and smoke more than 100 metres into the air after weeks of intense seismic activity.

Thousands of people have been evacuated and gas pollution could still occur in the area of the capital Reykjavik late on Tuesday evening or Wednesday morning.

Here are some of the images captured during and after the eruption.

The Icelandic Meteorological and Seismological Office (MET) reported late 18 December that a volcano erupted about 4 kilometers northeast of the town of Grindavik. Source: AAP / Iceland Civil Defense (almannavarnadeild)

Authorities last month relocated the nearly 4000 inhabitants of the fishing town of Grindavik about 40km southwest of capital city Reykjavik, letting them in intermittently to check on homes put at risk by the tremors.

Live footage of the eruption showed bright yellow, orange and red lava in sharp contrast against the sky.

Some tourists were in awe at the spectacle.

The earthquake occurred in southwest Iceland on the Reykjanes peninsula. Source: AAP / Anton Brink / EPA

"Our BnB hosts sent us a message that the volcano has erupted," a tourist from the Netherlands who gave his name as Wouter said.

"It's a once in a lifetime for us so we don't want to miss that... It's a bit far from here but you can still see some lava coming up, for us this is amazing."

There have been several eruptions in unpopulated areas on the Reykjanes peninsula in recent years. Source: Getty / NurPhoto

The eruption opened a 4km fissure.

But at its southernmost point the crack was still 3km away from Grindavik, Iceland's Meteorological Office said, and the power of the volcano was decreasing.

"The eruption is taking place north of the watershed so lava does not flow towards Grindavik," geologist Bjorn Oddson told public broadcaster RUV.

The eruption spewed lava and smoke more than 100 metres into the air. Source: AAP / Marco Di Marco/AP

Located between the Eurasian and the North American tectonic plates, among the largest on the planet, Iceland is a seismic hot spot because the two plates move in opposite directions.

The eruption is about 30km from Reykjavik.

The Blue Lagoon, a geothermal spa popular with tourists, has been largely closed since the seismic activity was detected.

"It could potentially go on for several months, it could also just stop later today or tomorrow," said Halldor Geirson, an associate professor at Institute of Earth Sciences at the University of Iceland.

Residents and tourists gathered to view the lava after the volcanic eruption. Source: Getty / Jeff J Mitchell

Lava flows had decreased from 200-250 cubic metres per second in the first two hours of the eruption to about a quarter of that by Tuesday morning.

Geirson said most of the lava was flowing into an area where there was little infrastructure.

Iceland's civil defence warned the public not to approach the area while emergency personnel assessed the situation after a volcanic eruption. Source: AAP / Anton Brink / EPA

Thousands of people were evacuated following weeks of seismic activity. Source: AAP / AP

A volcanic eruption began Monday night in Iceland, south of the capital Reykjavik. Source: AAP / Anton Brink / EPA