Mount Etna, one of world’s most active volcanoes, started erupting on Sunday forcing a suspension of flights at Catania’s international airport.

The Fontanarossa International Airport is closed until 1 pm CET, Aug. 14, the Italian carrier ITA Airways said in a tweet on Monday morning, after a layer of volcanic ash covered an area on the east coast of Sicily where the volcano is located.

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The eruption took place during the night in the southeast crater of the volcano at an altitude of about 2,700 meters, spewing smoke and ash, the National Institute of Geophysics and Volcanology said. The activity of the volcano is now improving, according to the last statement issued on the Institute website at 8:54 am CET.