'High' alert, wildfire threats after Iceland's Sundhnukur volcano erupts

July 16 (UPI) -- Icelandic authorities now say threats of wildfires have officials on "high" alert and that eruption fissures were bigger than scientists initially thought after Wednesday's eruption of the once-dormant Sundhnukur volcano.

"Seismic activity has decreased significantly and only a few small earthquakes are now measured per hour," according to Iceland's meteorological agency in a translated afternoon update.

The volcano alert level, it added, remained at its "highest level" as a possibility of wildfires remains. But it said ongoing threats of polluted air from the toxic substances was minimally detected and "not reflected in current pollution forecasts."

There have been no reports of injuries.

For its 12th time in four years, Sundhnukur in the Reykjanes Peninsula on the west southern tip of Iceland spewed smoke and volcanic lava in the air Wednesday morning in its latest activity after centuries of silence until 2021.

Tourists, families, hotel guests and the public in nearby resort towns were evacuated as a precaution in Grindavík, Blue Lagoon resort and other areas. However, despite this, no flight disruptions were reported at nearby Keflavík airport.

Initial reports indicated that liquid hot magma created a fissure in the Earth's crust around 2,296 feet and 3,280 feet long after an "intense earthquake swarm."

The GPS and deformation data originally suggested a minor eruption by comparison. A smaller crater also opened west of Fagradalsfjall, estimated to be roughly 1,640 feet long.

However, the afternoon update noted the eruption fissure "lengthened and extends further north than previous eruption fissures" since December 2003.

The agency said at the time that lava flow was concentrated and did "not threaten any infrastructure at this time."

High levels of gas pollution were reported by authorities in the municipality of Reykjanesbær after wind carried it but later decreased in toxicity. In its afternoon update, lava was reported flowing northeast from its source covering a large area on Kálffellsheiði and towards Svartsengi.

Since 2020, the Reykjanes Peninsula in southwestern Iceland has produced multiple volcanic eruptions and was active all last year in January through to November after earthquakes activated systems.

The town of Grindavík once housed around 4,000 Icelanders but was evacuated late last year and has reportedly largely remained a ghost town over safety due to ongoing volcanic risk as Icelandic authorities warned tourists to stay away from the area.

Iceland's Sundhnukur volcano was active as recently as early February and May of last year.