The White House has provided an update of sorts following a major system outage that grounded all U.S. flights early Wednesday, as criticism of Transportation Secretary Pete Buttigieg increased again.

“The President has been briefed by the Secretary of Transportation this morning on the FAA system outage,” White House Press Secretary Karine Jean-Pierre tweeted before 7:40 a.m. ET. “There is no evidence of a cyberattack at this point, but the President directed DOT [Department of Transportation] to conduct a full investigation into the causes. The FAA will provide regular updates.”

Fox News reported an “FAA system failure prompted massive flight delays Wednesday morning. All domestic departures were grounded until 9 a.m. ET, though the Federal Aviation Administration said some departures were resuming at Newark Liberty and Atlanta Hartsfield-Jackson airports ‘due to air traffic congestion in those areas.'”

The agency said it is working to restore the Notice to Air Missions system as quickly as possible.

According to its latest update, the FAA has ordered airlines to pause all domestic departures until 9 a.m. ET “to allow the agency to validate the integrity of flight and safety information.”

The report noted further:

At 8 a.m. Eastern, there were more than 2,500 delayed flights within, into or out of the United States, according to the flight tracking website FlightAware, exceeding the number of all delayed flights on the previous day. More than 150 have been canceled. Those numbers are likely to grow.

More than 21,000 flights were scheduled to take off in the U.S. today, mostly domestic trips, and about 1,840 international flights expected to fly to the U.S., according to aviation data firm Cirium.

President Biden talked about the issue Wednesday before departing the White House, noting that he had been briefed about the situation by Buttigieg who claimed officials still don’t know what happened.

“I just spoke to Buttigieg. They don’t know what the cause is. But I was on the phone with him about 10 minutes,” Biden said. “I told him to report directly to me when they find out. Air traffic can still land safely, just not take off right now. We don’t know what the cause of it is.”

“I have been in touch with FAA this morning about an outage affecting a key system for providing safety information to pilots,” Buttigieg wrote on social media Wednesday morning. “FAA is working to resolve this issue swiftly and safely so that air traffic can resume normal operations, and will continue to provide updates.”

I have been in touch with FAA this morning about an outage affecting a key system for providing safety information to pilots. FAA is working to resolve this issue swiftly and safely so that air traffic can resume normal operations, and will continue to provide updates.

— Secretary Pete Buttigieg (@SecretaryPete) January 11, 2023

“FAA has determined that the safety system affected by the overnight outage is fully restored, and the nationwide ground stop will be lifted effective immediately,” he wrote later. “I have directed an after-action process to determine root causes and recommend next steps.”

“The NOTAM outage continued with no current estimated time of restoration,” the FAA website stated Wednesday morning.

“Normal air traffic operations are resuming gradually across the United States following an overnight outage to the FAA’s Notice to Air Missions (NOTAM) system that provides safety information to flight crews,” the FAA said in a statement. “The ground stop has been lifted. The agency continues to look into the cause of the initial problem.”

Buttigieg’s tenure has been marred with criticism from both Democrats and Republicans, and this latest incident is only pouring fuel on the fire for those who find him incompetent to lead the agency, per Fox News:

The transportation secretary recently came under fire after it was revealed he vacationed in Porto, Portugal, while his agency and the White House were locked in tense negotiations with rail worker unions to avert a strike that could have had a dire impact on the U.S. economy. The Department of Transportation said the vacation was a “long-planned personal trip.” 

Buttigieg was also slammed for his handling of the supply chain crisis in 2021. Throughout the second half of the year, ships were forced to wait off the coast of California due to onshore logjams, as a trucker shortage slowed transportation and rail yards faced massive clogs.