A rare 5.6 earthquake, considered to be the strongest on record in the area, shook the central US state of Oklahoma late Saturday reportedly causing damage but no injuries. After initially putting the magnitude of the temblor at 5.2, the US Geological Survey revised the strength of the seismic event, the second of the day, saying it had reached magnitude 5.6.
The epicenter of the tremor, which occurred at 10:53 pm local time (0353 GMT Sunday), was located just six kilometers (four miles) east of the town of Sparks at a depth of five kilometers. KJRH television said the Lincoln County Emergency Management agency was reporting significant damage, but its extent was not immediately clear.
The Tulsa World newspaper quoted Lincoln County emergency manager Joey Wakefield as saying that portions of federal highway 62 had buckled and the chimney on a two-story house collapsed near the town of Prague. Other buildings were also damaged. "It was a pretty ornery little earthquake," Wakefield is quoted as saying.
The first 4.7-magnitude jolt was reported north of the town of Prague early Saturday. The readings were based on the open-ended Moment Magnitude scale, now used by US seismologists, which measures the area of the fault that ruptured and the total energy released.
The Oklahoman newspaper said the quake was felt as far away as north Texas. It quoted Michelann Ooten, a spokeswoman for the Oklahoma Department of Emergency Management, as saying that no injuries were reported to emergency management officials. But a lot of people were scared. "The picture by the TV fell off the wall and we jumped up because we thought somebody had hit the house," Oklahoma City resident Noeh Morales told The Oklahoman. "It was like a roaring noise. I've never heard one that bad over here."