Volcanic eruption remains highly likely in Iceland amid 'constant' seismic activity, officials say

There remains a "significant likelihood" of a volcanic eruption in the coming days in southwestern Iceland, the country's meteorological office said, as hundreds of earthquakes continue to shake the region.

About 800 earthquakes have been measured so far on Wednesday, with the main seismic activity in the area of the coastal fishing town of Grindavik, the Icelandic Meteorological Office said Wednesday morning. More than 20,000 quakes have shaken the area since late October, with seismic activity "constant" since Saturday, officials said.

"Most earthquakes are occurring along the magma intrusion, with the majority being micro-earthquakes," the Icelandic Meteorological Office said Tuesday.

Due to strong indications of an imminent eruption, officials declared a state of emergency near the Mount Fagradalsfjall volcano on the sparsely populated Reykjanes Peninsula. About 3,700 residents of Grindavik were told to begin evacuating on Friday, according to the Department of Civil Protection and Emergency Management.

As the region braces for a possible volcanic eruption, residents have been offered a last chance to go home to retrieve belongings and pets. Iceland authorities holding stopwatches gave residents on Wednesday five minutes to collect what they left behind when they evacuated.

The Blue Lagoon, a well-known thermal spa in the town of Grindavik, closed its doors Nov. 9, saying the chances of an eruption "have significantly increased." It will remain closed until at least the end of the month.

Fagradalsfjall, one of Iceland's most popular tourist attractions, has erupted three times since 2021, most recently in July.

ABC News' Kevin Shalvey contributed to this report.