Approximately 10,103 flights within, into or out of the United States have been delayed and 1,343 have been canceled as of 9:20 p.m. ET Wednesday, according to the flight-tracking website FlightAware.

The Federal Aviation Administration said Wednesday night it is "working diligently to further pinpoint the causes of this issue" behind the widespread cancellations and delays.

A government official familiar with the investigation into the Notice to Air Missions (NOTAM) system outage told CNN the Federal Aviation Administration (FAA) is still trying to determine who is responsible for the corrupted file identified in the probe first reported by CNN. The NOTAM outage grounded flights across the US.

The official said they aren’t sure the nature of how that corruption happened, whether it was a “routine entry” or one that was coded wrong.

In a new statement Wednesday night, the FAA acknowledged there was a “damaged database file.” The agency says the investigation is ongoing.

"The FAA is continuing a thorough review to determine the root cause of the Notice to Air Missions (NOTAM) system outage. Our preliminary work has traced the outage to a damaged database file. At this time, there is no evidence of a cyberattack. The FAA is working diligently to further pinpoint the causes of this issue and take all needed steps to prevent this kind of disruption from happening again," the statement read.