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-dorman

The eruption began early July 16 on the Sundhnúkur Crater Row, about 30 miles southwest from the capital, Reykjavik. See images of the eruption.

An official said the eruption near Reykjavik, the 12th in four years from the same volcanic system, posed no threat to people or infrastructure.