(CNN/Meredith) -- Mount Etna -- Europe's highest and most active volcano -- erupted on Monday, causing a magnitude 3.3 earthquake and the closure of Sicily's Catania Airport.

"Due to the eruption of #Etna from today 2pm (December 24th) #Catania airspace is closed," the airport tweeted.

The airport said that while it would be closed, some airspace would be reopened to allow four flights an hour to arrive.

It advised passengers to contact their airline before heading to the airport and confirmed that a "crisis unit" was expected to meet.

Etna's eruptions are relatively frequent and, according to Italy's National institute of Geophysics and Volcanology, there has been a gradual increase in activity on the volcano over the last month.

Recommended for you

(0) comments

Welcome to the discussion.

Keep it Clean. Please avoid obscene, vulgar, lewd, racist or sexually-oriented language.
Don't Threaten. Threats of harming another person will not be tolerated.
Be Truthful. Don't knowingly lie about anyone or anything.
Be Nice. No racism, sexism or any sort of -ism that is degrading to another person.
Be Proactive. Use the 'Report' link on each comment to let us know of abusive posts.
Share with Us. We'd love to hear eyewitness accounts, the history behind an article.