Seen from a distance, Sunday's eruptions greet the Icelandic countryside like a sunrise.
The lava fountains on Eyjafallajoekull volcano, which is 5,466 feet (1,666 meters) tall, threatened to melt parts of the adjacent Eyjafjallajokull glacier, sparking fears of flooding in the sparsely populated farmland below.
"We estimate no one is in danger in the area, but we have started an evacuation plan, and between 500 and 600 people are being evacuated," Sigurgeir Gudmundsson of Iceland's civil-protections agency told the AFP news service Sunday.
Late Sunday some residents from the outskirts of the evacuation zone were permitted to go home as floods failed to materialize. Scientific overflights Monday aimed to determine whether the rest of the evacuees could do the same, the Associated Press reported.
(Related: "Under-Ice Volcano Eruption Spewed Ash Over Antarctica.")