Survey officials say the earthquake was centered in the Old Greenwich neighborhood and struck shortly before 9 p.m. No injuries or damage have been reported.
Dozens of people called Stamford police to report that they felt their homes shake.
Greenwich sits on an earthquake fault line that runs along the shoreline to Branford.
It was just over a year ago that people in southern New England felt the 5.8-magnitude quake centered near Richmond, Va., that caused damage near the epicenter and in Washington, D.C.
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