Officials say the injuries were minor and were caused by falling debris from damaged buildings. It forced the temporary closure of Sicilian airspace because of clouds of smoke and ash, which coated nearby villages.
Italy's Civil Protection officials said the quake, at 3.19am Wednesday, was part of a series of some 1,000 tremors, a lot of them barely perceptible, that are linked to Etna's ongoing eruption this week.
A chain of around 130 tremors have rocked the volcano since around 9am on Monday, Italy's National Institute for Geophysics and Volcanology said.
Although the natural disaster hit to the north of Catania, the largest city in eastern Sicily, no damage or injuries were reported there, but other towns experienced cracks opening in buildings, while a number of villagers fled their homes in panic. None of the injuries were serious.
Some 18 other people went to local hospitals suffering from panic attacks or shock, news reports said.
An 80-year-old man was pulled from the rubble of a house, the Italian news agency ANSA said.
Lava was also observed emerging from a fissure in the side of Mount Etna, which is also known as a "flank" or lateral eruption.
Etna has seen frequent activity since July.