Lava and ash spewed from a new fracture on Mount Etna, Europe's biggest active volcano, on Monday.
More than 130 seismic shocks were recorded before midday, with the strongest reaching a magnitude of 4.0, according to Italy's National Institute of Geophysics and Volcanology (INGV).
Hikers in danger
"The eruption occurred on the side of Etna," said Boris Behncke, a vulcanologist at INGV. "It's the first lateral eruption in more than 10 years, but it doesn't seem to be dangerous."
There were no immediate reports of injuries or disruption to local residents.
Hikers were brought down from higher elevations to 1,900 meters (6,230 feet) for their safety.
Flights were restricted to just four landings an hour at the nearby airport at Catania because of poor visibility.
Read more: If you live near one of these volcanos, move!
Etna formed some 500,000 years ago off the ancient coastline of Sicily. It usually experiences small eruptions every few months.
The mountain stands 3,300 meters (3,609 yards) high.
Its most recent eruptions occurred in August and in the Spring of 2017, resulting in a spectacular light and ash show.
The last major eruption was in the 2008/2009 winter.
Mount Etna was granted UNESCO heritage status in 2013.
kw/jm (AP, AFP, Reuters)
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