Officials in Philadelphia had no explanation Saturday for residents who felt their homes shake from what they thought was an explosion, the Philadelphia Inquirer reported. Police, firefighters and other emergency responders were dispatched to northeast Philadelphia after hundreds of residents reported feeling the ground shake shortly before 10:00pm Friday.
Resident Edward Turzanski described hearing "a loud bang," then feeling "a sharp jolt from below."
No fires, explosions damaged homes or injuries were found. The US Geological Service said it had no seismological evidence of an earthquake or tremor.
A representative for power company Peco Energy said there were no reports of power outages, and the Philadelphia Water Company said there was no evidence that any pipes had burst, the paper said.
The Philadelphia Fire Department declared the situation to be under control at 10:45pm, and emergency crews left the area around 11:30pm.
The mysterious tremors were also felt in lower Bucks County, Pa., about 50 miles (80 kilometers) north of Philadelphia, according to the report. Source
