A new fissure which has opened in the Sicilian volcano Mount Etna is the first for over a decade, according to volcanologists.

The “flank eruption” occurred around midday on Christmas Eve during a phase of unusually high seismic activity which shut down airports and caused more than 300 tremors.

Lava and ash spewed from the vent which opened near Etna’s southeast crater, and was visible for miles around.

Etna’s last major eruption was in 1992 but Boris Behncke, a researcher at the Etna Observatory of the Italian National Institute of Geophysics and Volcanology (INGV), said there had been flank eruptions this century.

Writing on Twitter, Mr Behncke said the start of the new fissure opened “shortly after noon on 24 December 2018”.

Hikers were told to come down to lower elevations to avoid the noxious fumes being released, but there were no reports of injuries, while spewing ash was not causing major disruptions to nearby residents.

Catania airport was forced to close temporarily, however, causing delays for travellers.

Etna, the largest of Italy’s three active volcanoes at 3,330m, has been particularly active since July. Its last major eruption took place in 1992.

Eugenio Privitera, director of the Etna Obervatory, said: “From nine o’clock in the morning we started seeing a swarm of tremors.”

“So far we have registered more than 300 tremors, most of them are located at a small depth, near the craters surrounding the peak.