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A senior Obama administration official played down the role of the federal government, saying state and local authorities were handling the situation.

“There will be no federal response,” the official said. “We have checked in with all impacted states, and none of them have any issues or damage that require federal assistance.”

A spokesman for the U.S. Nuclear Regulatory Commission (NRC) told The Times that the two reactors at the North Anna, Va., nuclear power plant, a few miles from the epicenter of the quake, had shut down automatically when the plant lost off-site power.

“Everything appears to be working as it should, and the plant is in a safe condition,” said NRC spokesman David McIntyre.

The earthquake was classified as an “unusual event,” the lowest emergency event classification, by 12 other nuclear power plants in Maryland, Michigan, New Jersey, Pennsylvania, and Virginia, he added. North Anna was the only plant reporting an “alert” status, the second-lowest classification level, and shut down.

The last earthquake in the D.C. area was in July 2010, when a 3.6 magnitude quake was centered near Germantown in Montgomery County. The last earthquake in the area of a similar magnitude to the one Tuesday was a 5.7 magnitude quake in Virginia’s Giles County in 1897.

Central Virginia is relatively prone to minor seismic activity, with small earthquakes striking the area as often as once every year or two, according to information provided on the geological survey’s website.

According to the geological survey, earthquakes east of the Rockies are typically felt over a much larger region — sometimes as much as 10 times larger — than those that occur on the West Coast. A 5.5 magnitude earthquake on the East Coast is typically felt as far as 300 miles away and can cause damage over as much as a 25-mile radius.

George Foresman, a former senior homeland security official who worked for the federal and Virginia governments, said that while the quake appeared to have caused little damage, it was nonetheless “a teachable moment … in the shadow of the Sept. 11 [10th] anniversary.”

“It’s a reminder to us all to dust off our emergency plans,” he said. “In general, people seem to have reacted well, apart from the cellphone thing,” said Mr. Foresman, calmly evacuating buildings and following safety procedures. “But it should be a reminder to all of us about the importance of preparedness at all levels — personal, corporate and government,” he said.

Tom Howell Jr., Dave Boyer and Shaun Waterman contributed to this report.