Oklahoma, August3:An quake registering 4.2 on the richter scale in central Oklahoma, US, damaged power supply lines, disrupting supply to hundreds of customers.
The fourth natural disaster was reported 3:45 p.m. Wednesday and was a 3.3 magnitude.
The U.S. Geological Survey initially reported the 4.4-magnitude tremor was detected at 9:56 p.m. Wednesday about 4 miles (6 kilometers) east-northeast of Edmond, Oklahoma - about 15 miles (25 kilometers) northeast of Oklahoma City.
Originally registering as a 4.4, the survey lowered the magnitude slightly to 4.2.
At least seven earthquakes have struck the Oklahoma City area in the last three days, including one that knocked out electrical service to nearby residents.
The Oklahoma Corporation Commission's Induced Seismicity Department and the Oklahoma Geological Survey are investigating the recent Edmond-area earthquakes.
This left around 1900 customers in the dark until crews could fix the stations and restore power. The quake was the sharpest of six tremors detected in the Edmond area over a 24 hour period.
No injuries or significant damage have been reported. Each had a magnitude of 3.0 or stronger. The second was a 3.5-magnitude about 12:15 a.m. and the third was a 3.0-magnitude at 2:45 a.m.
The Oklahoma Corporation Commission, the state's top oil and gas regulator, is reviewing the wells' recent operations. Emergency management officials are working to determine possible damage as a result of the larger quake.