Italy's Mount Etna emitted an ash cloud rising about 4 kilometers (2.5 miles) on Thursday, prompting the country's volcanology institute to issue its highest aviation alert, according to Rai News.
The National Institute of Geophysics and Volcanology's Etna Observatory in Catania issued a red Volcano Observatory Notice for Aviation as ash from the volcano's summit craters dispersed toward the south-southeast, the broadcaster reported.
Volcanic tremors remained at medium-low levels.
The activity had not affected operations at Catania's Vincenzo Bellini International Airport at the time of the report.
