Undated (AP) _ A strong earthquake rumbled beneath nine Great Lakes and Ohio Valley states, the District of Columbia and Canada today. Some damage was reported but there were no reports of injuries.

The quake was reported felt in Pennsylvania, Kentucky, Ohio, West Virginia, Indiana, Illinois, Michigan, New York and Wisconsin and as far north as Barrie, Ontario. Ira Stohlman, a City Council staff member in Washington, D.C., said the city government building two blocks from the White House shook.

The U.S. Geological Survey in Washington, D.C., estimated that the quake, which occured at 11:47 a.m. EST, had a magnitude of 5.0 on the Richter scale of ground movement and was centered 30 miles northeast of Cleveland.

Waverly Person of the agency's office in Golden, Colo., said the quake was believed to be centered in Lake Erie. But Gail Wendt of the Geological Survey's Reston, Va., office said later that the epicenter was in Geauga County, Ohio, just east of Cleveland.

Police stations, newspapers and broadcast stations were flooded with calls.

A 4-foot crack was reported in the municipal building in Sharon, Pa. Mayor Bob Price said the building shook and city employees fled into the street.

In Lake County, Ohio, schools and businesses were evacuated, according to the Lorain Journal.

"My house shook pretty good, like somebody was shoving it around every way they wanted to," said Pat Barco of Meadville, Pa.

Paul Oles, planetarium director of the Buhl Science Center in Pittsburgh, described the quake as "moderately strong."

"The ground (in the East) is fairly stable. It's rare to have an earthquake of this magnitude in this area," he said.

In Niagara Falls, Ontario, a spokesman for the fire department said buildings shook all across the city.

"The chairs were shifting on the floor," said Platoon Chief Hector Lapierre, who was attending a meeting. "It lasted about 30 seconds."

In Detroit, downtown office buildings jiggled. A woman who did not identify herself at the Detroit Public Library said records showed the last tremor to hit the nation's sixth-largest city occurred on July 27, 1980. That quake, centered in Kentucky, measured 5.6 to 5.7 on the Richter scale.

Cleveland Electric Illuminating Co. spokesman Lee Bailey said the earthquake knocked out a 650 megawatt generator at the company's Eastlake coal-burning plant. However, other generators picked up the slack.

In the Chicago suburb of Des Plaines, Dale Kemery, president of Kemery Media Co., said that as a former California resident, he immediately realized the shaking he felt was an earthquake.

"All of a sudden, this building started rolling underneath me," he said. "I sat here about 15 seconds watching the plants sleighing to and fro."

He said his business suffered no damage.

The Richter scale is a measure of ground motion as recorded on seismographs. Every increase of one number means a tenfold increase in magnitude. Thus a reading of 7.5 reflects an earthquake 10 times stronger than one of 6.5.

An earthquake 3.5 on the Richter scale can cause slight damage in the local area, 4 moderate damage, 5 considerable damage.

The San Francisco earthquake of 1906, which occurred before the Richter scale was devised, has been estimated at 8.3 on the Richter scale.

While Alaska and California are perhaps best known as earthquake sites in the United States, ground movement is not uncommon in the East. The U.S. Geological Survey estimates that 3,500 quakes have been felt east of the Mississippi River since 1700.

While New Madrid, Mo., was the site of the most powerful quake in U.S. history, in 1811-12, others have shaken Boston, Charleston, S.C., and New York City, among other communities.

The area northeast of Cleveland, where today's quake was centered, was also shaken in 1943.

That tremor, in early March, was felt over about 40,000 square miles. However, damage was relatively slight, with cracked windows and broken dishes the main problems reported.

Since 1875, 22 earthquakes with an intensity of V or greater on the Modified Mercalli Scale have centered within Ohio. Several caused moderate damage.

The Modified Mercalli Scale reflects the effects of an earthquake on the populaton rather than merely the force of ground motion. A V on the Mercalli Scale identifies an earthquake felt by nearly everyone and in which unstable objects can be overturned.

The most frequent and damaging earthquakes in the state have originated near the western Ohio town of Anna, in Shelby County.