The Icelandic Meteorological Office said on Monday that there was still a "significant likelihood" of a volcanic eruption on the Reykjanes Peninsula in the coming days despite a decrease in seismic activity.

The seismic activity in Grindavik, a town of roughly 4,000 people near Reykjavik, caused hundreds of small earthquakes that damaged roads and buildings.

"We believe that this intrusion is literally hovering, sitting in equilibrium now just below the earth's surface," said Matthew James Roberts, director of the service and research division at the meteorological office.

"We have this tremendous uncertainty now. Will there be an eruption and if so, what sort of damage will occur?"

Grindavik residents pack their belongings

Residents of Grindavik, who were told to leave the town in the early hours of Saturday morning, were allowed to briefly return to their homes to collect their belongings on Monday.

Cars lined up for hours outside the evacuation zone and were allowed in for just a few minutes at a time.

"We ask everyone to take as short a time as possible," Iceland's emergency response department said in a statement.

Residents could be seen filling their cars to the brim with furniture, paintings and in one case even sheep.

A history of seismic activity

The Reykjanes Peninsula seismic hotspot lies southwest of Iceland's capital.

"We have a fissure that's about 15 kilometers (roughly 9 miles) long, and anywhere on that fissure we can see that an eruption could happen," Vidir Reynisson, head of Iceland's Civil Protection and Emergency Management agency, told the AFP news agency on Saturday.

In March 2021, lava fountains erupted from a fissure in the ground measuring between 500-750 meters long in the region's Fagradalsfjall volcanic system.

Two other eruptions from the same system occurred in August 2022 and July 2023.