The U.S. Geological Survey reports the epicenter was located one mile north of Gaithersburg in Germantown, although the rumbling was felt over a widespread area from Frederick to Washington, D.C., to Virginia.

Gaithersburg City Council member Michael Sesma was one of many awakened by the earthquake.

“Thought at first it was a sonic boom or an unusually low jet in very humid air but then realized what it was,” said Sesma.

Some Gaithersburg residents thought it was some kind of an accident.

“I thought a train derailed or stopped quickly as I live next to the tracks,” Tom Rowse said on The Town Courier’s Facebook page. “I then went outside and no train. Wow!”

“Sure woke me up, I thought a car had hit the house,” wrote Gaithersburg City Council member Cathy Drzyzgula on her Facebook page.

Ellen Rutt was awake when the quaking began.

“The bed shook and things rattled on the tables in our bedroom,” Rutt reported.

Lakelands resident Jodi Quinn said she and her husband felt it, too.

“Freaked me and Chris out,” she said on her Facebook page. “Felt like something hit our building. The whole thing shook.”

Debi Rosen said the rumbling woke her up in Rockville.

“I thought there was an explosion close to our home,” she said. “I turned on the news sure to hear of some catastrophe … and heard it was an earthquake.”

Despite living in California for two years, it was Kentlands resident Carrie Dietz’s first earthquake.

“I had to move to Maryland to experience my first one,” she wrote on her Facebook page. “Very wild experience.”

At press time, there were no reports of damage or injuries elsewhere.

MedImmune officials said they were not aware of any impact from the earthquake on facilities at the corporate headquarters site in Quince Orchard Park. Still, they were not taking any chances at the nearby construction site.

“In an abundance of caution, we have shut down the tower cranes until they can be inspected,” said Liz Huntley, community affairs senior manager.

For more information about the earthquake, www.earthquake.usgs.gov/earthquakes/recenteqsus.

The U.S. Geological Survey reports the epicenter was located one mile north of Gaithersburg in Germantown, although the rumbling was felt from Frederick to Washington, D.C.

Gaithersburg City Councilman Michael Sesma said the earthquake woke him up.

“Thought at first it was a sonic boom or an unusually low jet in very humid air but then realized what it was,” said Sesma.

Gaithersburg resident Tom Rowse said he thought it was a train.

“I thought a train derailed or stopped quickly as I live next to the tracks,” he said on The Town Courier’s Facebook page. “I then went outside and no train. Wow!”

Ellen Rutt was awake when the quaking began.

“The bed shook and things rattled on the tables in our bedroom,” Rutt said.

Rockville resident Debi Rosen said the earthquake woke her up too.

“I thought there was an explosion close to our home,” she said. “I turned on the news sure to hear of some catastrophe … and heard it was an earthquake.”

So far, there have been no reports of damage or injuries.

For more information, www.earthquake.usgs.gov/earthquakes/recenteqsus