It was the largest quake in Virginia since 1897 and struck at a shallow depth, increasing its potency.

Nuclear safety fears grew when one of four emergency diesel generators at the North Anna nuclear power plant in Virginia stopped working due to the quake.

But the plant's safety systems remained powered by three operating generators, the Nuclear Regulatory Commission said. The plant was built to withstand a quake of 6.1 magnitude.

The Pentagon, White House and Capitol were evacuated in Washington, and thousands of alarmed workers scurried into the streets up and down the East Coast as the lunchtime quake sent items crashing down from store and office shelves.

Washington's National Cathedral, host to state funerals and memorial services for many U.S. presidents, suffered damage with three spires in the central tower breaking off.

The East Coast does not normally experience quakes as strong as Tuesday's. The U.S. Geological Survey said the quake was of 5.8 magnitude, downgrading an earlier estimate if 5.9.

Earthquakes of magnitude 5.5 can cause damage to buildings and other structures.

In addition to the Virginia earthquake, there were nine tremors in the area immediately around Cokedale, Colorado, near the border of New Mexico.