A 5.6-magnitude earthquake struck central Oklahoma late Saturday night - the largest to hit the state since record-keeping began.
The quake struck 4 miles east of Sparks in Lincoln County at 11:53 p.m. ET, the United States Geological Survey said.
There were no immediate reports of damage.
It was the same area where a 4.7-magnitude quake struck at 3:12 a.m. ET Saturday. By 8 a.m., geologists had recorded more than 30 aftershocks from it.
The strongest quake previously reported was of magnitude 5.5 on April 9, 1952, according to the Oklahoma Geological Survey.