Authorities say a powerful earthquake has shaken Greece's southeastern island of Rhodes, but no injuries or damage have been immediately reported. The Athens Geodynamic Institute says the quake with a preliminary magnitude of 5.8 struck beneath the Aegean Sea at 3:44 p.m. (1244 GMT) Sunday, about 490 kilometers (305 miles) east of Athens. That is between the Greek island of Rhodes and western Turkey. The institute says the temblor occurred at a depth of 37 kilometers (23 miles). Police in Rhodes say there are no reports of injured people or damage. Greece is in one of the world's seismically active areas, with hundreds of quakes occurring each year.