A 5.9 magnitude earthquake jolted the East Coast, rattling people from Martha's Vineyard to Washington, D.C. to North Carolina, prompting the evacuation of Congressional buildings, slowing rail and air traffic, and taking two nuclear reactors offline.

The earthquake sent people pouring out of office buildings, hospitals, the Pentagon and the State Department. The pillars of the capitol in Washington, D.C. shook. Alarms sounded in the FBI and Department of Justice buildings, and some flooding was reported on an upper floor of the Pentagon as a result of the quake.

Parks and sidewalks in Washington were packed with people who fled their buildings. Police on horseback are keeping people a safe distance from getting too close to the Washington Monument and Jefferson Memorial.

Officials are inspecting Congressional buildings before members of Congress and their staff can return to their offices.

The quake was felt as far north as New Hampshire and in Martha's Vineyard where President Obama and his family are vacationing. It was felt as far south as South Carolina.

No significant damage or fatalities have been reported. Some injuries have been reported in Washington D.C., the fire department spokesman told the Associated Press. In New York City, the fire department said that they are receiving a surge in calls but have had no serious building damage reported.

Authorities in New York and Washington said cell phone traffic was so heavy that it hampered their ability to respond to emergencies.

The epicenter of the quake was near Mineral, Va., 39 miles from Richmond, Va., and 85 miles from the nation's capital. The quake was .6 miles deep.

According to convertalot.com, a web site which compiles measurements and calculators for a variety of statistics, the magnitude 5.9 earthquake released energy equivalent to the explosion of 10,676 tons of TNT.

The epicenter of the quake is very close to two Dominion Power nuclear power plants, North Anna 1 and 2.

Rare 5.9 East Coast Earthquake

Elizabeth Stuckle, spokesperson for the Nuclear Regulatory Commission, said that the reactors were "automatically and safely shut down." The plant declared an "unusual event" which is the lowest category of four emergency classifications. Back-up generators automatically kicked in to keep the reactors cool, the NRC said.

Nine other nuclear plants on the East coast declared an "unusual event," but were none shut down.

The East Coast gets earthquakes from time to time, but rarely of a magnitude to make skyscrapers sway.

Paul Segall, a Stanford geophysicist who studies the structure and development of earthquake faults, called today's shaker "a significant earthquake for that part of the world. It could do significant damage."

"I can't remember an event that large on the East Coast," he said.

The tremblor affected travel in the region.

Amtrak said it was running at reduced speed and was checking tracks and terminals for damage. The Washington Metropolitan Area Transit Authority said the Metro is moving at 15 miles per hour as inspectors check all tracks.

Officials at Reagan National Airport in Washington and JFK International Airport in New York temporarily halted flights and the control towers at Reagan, JFK and Newark International airports was temporarily evacuated. The delay will cause slow air traffic throughout the region, the Federal Aviation Administration warned.

A woman who works at Mineral Barber Shop in Mineral, Va. said that the inside of her shop is a mess but there doesn't appear to be any major damage outside the town square.

People in the New York Times building on 42nd street in Manhattan said they felt the entire building shift, and watched office furniture move. As the tall buildings in New York swayed, people ran out into the street.

The New York City Criminal Court in lower Manhattan was also evacuated.

The earthquake felt along the eastern corridor follows an earthquake felt Monday in Colorado. That 5.3 magnitude earthquake struck near Trinidad, Colorado.

The United States' Geological Survey said that earthquakes have been felt in the central Virginia area since 1774.

I will continue to post updates as news comes in.  If anyone has any details about the quakes, please feel free to share them.