According to local authorities, six of the injured were taken to hospitals in Catania and Acireale and are being treated for burns, but nobody is in a serious condition.
The explosion took place on Etna's Belvedere near Nicolosi when lava touched the snow on the volcano's peak, sparking a so-called "phreatic explosion" at an altitude of 2,700 metres.
Pyroclastic material was sent flying like shrapnel and hit the group of trekkers, which included three British tourists and BBC crew members.
Rebecca Morelle, global science correspondent for BBC News, reported that her crew had been involved in the incident via Twitter.
"Caught up in incident at Mount Etna - bbc crew & tourists caught up in huge explosion - caused injuries and evacuation from scene," she wrote.
"Lava flow mixed with steam - caused huge explosion - group pelted with boiling rocks and steam.
"Many injured - some head injuries, burns, cuts and bruises. Volcanologist said most dangerous incident experience in his 30 year career. Bbc team all ok - some cuts/ bruises and burns. Very shaken though - it was extremely scary."
With ANSA
