REYKJAVIK, Iceland – Iceland’s most active volcano has started erupting, scientists said Saturday — just over a year after an eruption on the North Atlantic island shut down European air traffic for days.

Iceland’s Meteorological Office confirmed that an eruption had begun at the Grimsvotn volcano, accompanied by a series of small earthquakes. Smoke could be seen rising from the volcano, which lies under the uninhabited Vatnajokull glacier in southeast Iceland.

A no-fly zone has been designated for 120 nautical miles in all directions from the eruption. Isavia, the company that operates and develops all airport facilities and air navigation services in Iceland, described this as standard procedure around eruptions.

“The plume of smoke has reached jet flying altitude and plans have been made for planes flying through Icelandic air control space to fly southwardly tonight,” said a spokeswoman for Isavia.

Grimsvotn last erupted in 2004. Scientists have been expecting a new eruption and have said previously that this volcano’s eruption will likely be small and should not lead to the air travel chaos caused in April 2010 by ash from the Eyjafjallajokull volcano.

History shows that previous eruptions in Grimsvotn have not had much influence on flight traffic — unlike the massive disruption caused last year.

Pall Einarsson, geophysicist at the University of Iceland, said last year’s eruption was a rare event. “The ash in Eyjafjallajokull was persistent or unremitting and fine-grained,” Einarsson said.