BOSTON.COM: The Seabrook nuclear power plant declared “an unusual event’’ at 7:20 p.m. Tuesday after an earthquake centered in Maine was felt in the control room of the New Hampshire facility, according to the Nuclear Regulatory Commission. In a statement, the NRC said the “unusual event’’ is the lowest of four levels of emergency classifications used by the NRC.

“The declaration was prompted by on-site ground motion resulting from an earthquake centered near Hollis, Maine – about 50 miles from the plant,’’ NRC spokesman Neil Sheehan said in a statement. (READ MORE)