There's been reports of a very strong earthquake near the islands of Kasos. USGS reporting a magnitude 6.0 quake. The tsunami warnings that followed were quickly dropped, but tremors were felt over much of the eastern Med.
https://earthquake.usgs.gov/earthquakes/eventpage/us7000pz2p/executive
https://earthquake.usgs.gov/earthquakes/eventpage/us7000pz2p/executive