LOUISVILLE, Ky. (WDRB) -- A nationwide cell phone outage early Thursday prevented some users from calling 911 for a few hours in a few local counties.

We still don't know the exact cause, but most phones are working again.

Thursday's nationwide outage was the second within a week. While the carrier worked to restore service, it suggested customers use Wi-Fi to make calls by turning on the feature in the settings menu. You will need an internet connection to make Wi-Fi calls. 

On Thursday, Metro Safe 911 said roughly 200 calls came in before noon from people checking to see if 911 still worked. 

"That's way more than there should have been," said Trevin Hunter with Louisville Metro Emergency Services. "We're hearing them call 911 and saying 'Oh I just wanted to make sure my phone works.' But we need to make sure those 911 lines stay available for actual emergencies."

Louisville Mayor Craig Greenberg said there was more than a "30 percent spike in 911 calls with people just reaching out." 

Officials urge people not to do that. 

"Use 911 for emergencies, and don't call it to test your phone," Hunter said. 

The website DownDetector, which tracks customers' reports of outages, shows nationwide AT&T outages spiked just before 5 a.m. That's when most people began reporting phone or internet troubles -- or no signal at all.

While MetroSafe uses an AT&T system, the outage didn't impact downtown Louisville. But officials said their contingency plan was to create a 10-digit phone number like Oldham County did when its 911 lines went down during the outage.

Although issues were reported with other cell phone carriers, both Verizon and T-Mobile said their network is fine, and and that problems only happened when their customers tried calling people who use AT&T.

So far, no reason has been given for the outages. But Lee McKnight, an associate professor in the iSchool at Syracuse University, believes the most likely cause of the outage is a cloud misconfiguration, or human error, according to an Associated Press article. 

"A possible but far less likely outcome is an intentional malicious hack of ATT’s network, but the diffuse pattern of outages across the country suggests something more fundamental," McKnight said in an emailed statement.

Another wireless industry source, Kurt Knutsson -- known as Kurt the Cyber Guy -- agreed that there is no indication it was caused by a cyberattack or other malicious activity, but noted that it is unusual.

"This just doesn't happen," he said. "You just don't have multiple wireless networks go down simultaneously and have this level of outage."

Officials said the outage is a good reminder to have at least two ways of getting emergency information. Louisville residents can text "LENSAlert" to 67283 to start receiving emergency notifications.

Copyright 2024 WDRB Media. All rights reserved. The Associated Press contributed to this report.