A new report says Oklahoma is seeing a sharp increase in earthquakes.
The Oklahoma Geological Survey said Monday that the state recorded 521 earthquakes on Sept. 22.
It also recorded a total of 762 aftershocks, or temblors.
Oklahoma is the most seismically active state in the nation, according to the National Earthquake Information Center.
The latest quake is also the most powerful since April.
Scientists said the magnitude of the quake could be the strongest since a magnitude 5.3 temblor hit Oklahoma City in April 2021.
The quake came on the heels of a series of earthquakes that struck Oklahoma and neighboring states, including the Oklahoman.
Mary Fallin called the temblorets “unprecedented” and a “national disaster” and declared a state of emergency.
The state has been under a federal alert for the temblets.
The National Weather Service issued a second alert Monday, saying temblores are expected to continue for a few more days.