From Claude Grandpey blog about yesterday Etna;s swarm
[link to volcans.blogs-de-voyage.fr
"...The strongest quake reached M 3.9 and was followed by about 10 others that were less powerful..."
INGV shows different data, at least two eqs over 4:
at 09:10 - 4,2 and at 11:25 4,3
[link to www.ct.ingv.it
and another remarkable thing:
"According to INGV volcanologist Boris Behncke, the seismicity may be linked to the underthrusting of African lithosphere between the European continental margin, but there is also speculation about a possible (though purely hypothetical) relationship with deep magma movement below Etna. As far as I’m concerned, I do not believe in this last hypothesis"
I guess Claude here wrong.