The Bardarbunga volcano in Iceland began erupting just a few minutes after midnight on Friday, local time, the Icelandic Met Office said.
You can watch a live video feed of the eruption here from webcams opertated by the Icelandic site Mila.
The eruption started in Holuhraun north of Dyngjujökull on Aug. 29, the Met office said in a statement.
"Seismic tremor was observed on all seismic stations and the web camera installed in the area by Mila has showed some nice pictures of the eruption."
The agency said that by around 2:40 a.m. the small fissure eruption appeared to calmed down.
"Air traffic has not been affected by eruption," the Icelandic news site mbl.is said in a tweet.