An unusually strong magnitude 5.8 earthquake struck central Virginia Tuesday afternoon and sent tremors along the East Coast, which prompted office buildings from Washington D.C. to New York to be evacuated.
There were no immediate reports of injury or serious structural damage.
The earthquake struck near Mineral, Va., more than three miles below sea level, the U.S. Geological Survey said. Mineral is town 83 miles from D.C. and has been known for its seismic activity, but seldom produces a substantial earthquake.
Most of downtown D.C. was evacuated, including the U.S. Capitol, the Pentagon and other office buildings. Pictures on the wall in the Capitol building reportedly fell and panicked workers ran to the exits, apparently fearing a 9/11-style attack. Workers were initially told not to re-enter the buildings, but were later allowed to enter the Capitol building.
Marine helicopters were seen hovering above the D.C, and there were reports that the Washington Monument may be tilting.
The National Park Service later completed a secondary inspection of the Washington Monument and found some cracking in the stones at the top of the Monument, according to a press release.
The NPS will have structural engineers evaluate the cracks on Wednesday to determine the best way to repair the Monument before reopening it to the public, said the statement.
The press corp with President Obama in Martha's Vineyard said they felt slight shaking. Obama told reporters that he did not feel the tremor. Attorney General Eric Holder has been evacuated from the Department of Justice.
Obama and many of the nation's leaders were out of town on August vacation when the quake struck at 1:51 p.m. local time.
"People pouring out of buildings and onto the sidewalks and Into Farragut Park in downtown DC...," GOP strategist Kevin Madden tweeted, MyFoxDC.com reported.
At Reagan National Airport outside Washington, ceiling tiles fell during a few seconds of shaking. Authorities put all flights on hold.
A spokesman for Washington National Cathedral said at least three of the four pinnacles on the central tower have fallen off and the central tower appears to be leaning.
New York also felt tremors from the earthquake.
Buildings in New York City shook briefly and the FBI building was evacuated. Flights resumed at John F. Kennedy International Airport and Newark Airport, where control towers were previously evacuated. Evacuations were demanded as north as Canada.
Federal officials say two nuclear reactors were taken offline near quake site in Virginia; there was no damage reported. Indian Point, a power plant in New York, said on Twitter that there are no issues at the facility.
The Federal Emergency Management Agency (FEMA) said in a statement that it is monitoring the situation and in "close contact" with federal and state partners.
The East Coast gets earthquakes, but usually smaller ones and is less prepared than California or Alaska for shaking. The Washington area has had small, infrequent earthquakes over the years, including a 2.5-magnitude quake in 1997 that was within 25 to 30 miles of Friday's quake and a 2.3-magnitude quake in 1996 that was within 15 miles
Phone companies said they are being overwhelmed with phone calls, but said none of their infrastructure have been damaged.
FEMA requested that the public use e-mail or text messages in non-emergency cases so emergency officials can continue to receive and respond to urgent calls.
U.S. weather service says no tsunami expected after East Coast.
Subways in New York have not been affected, but the Metro in D.C. had been temporarily cancelled.
Amtrak said its trains along the Northeast Corridor between Baltimore and Washington were operating at reduced speeds and crews were inspecting stations and railroad infrastructure before returning to normal, crews have since finished the inspection and operations have reportedly returned to normal.
The Associated Press contributed to this report.