A cellular outage early on Thursday hit thousands of AT&T users in the United States, disrupting calls and text messages as well as emergency services in major cities including San Francisco.
About 70,000 incidents were reported around 10:00 a.m. ET, according to data from outage-tracking website Downdetector.com. The cause of Thursday’s outage was not immediately clear.
“Some of our customers are experiencing wireless service interruptions this morning,” AT&T said in a statement to CNBC. ”We are working urgently to restore service to them. We encourage the use of Wi-Fi calling until service is restored.”
A spike in outages began around 4:00 a.m. ET and peaked at around 74,000 reported incidents at 8:30 a.m. ET, according to Downdetector.
Shares of AT&T were down about 2% Thursday morning following the outages.
The AT&T outage has impacted people’s ability to reach emergency services by dialing 911, a post on social media platform X from the San Francisco Fire Department said.
“We are aware of an issue impacting AT&T wireless customers from making and receiving any phone calls (including to 911),” the fire department said on the platform.
Atlanta Mayor Andre Dickens said in a post on X that the city can receive and make outbound 911 calls but that AT&T customers in the area had reported issues.
“We have received calls from AT&T customers that their cellular phones are in SOS mode. Please direct all inquiries to restore service to AT&T,” Dickens said.
The Massachusetts State Police said that people were flooding their 911 center with calls trying to determine if the service works from their cell phones.
“Please do not do this. If you can successfully place a non-emergency call to another number via your cell service then your 911 service will also work,” the state police said in a post on X.
Users of Verizon and T-Mobile were reporting a few thousand outages each as of 10:00 a.m. ET, according to Downdetector.
These reports were likely due to calls made trying to connect with other networks, both companies said.
“Downdetector is likely reflecting challenges our customers were having attempting to connect to users on other networks,” T-Mobile said in an emailed statement.
– Reuters and CNBC’s Steven Kopack contributed to this report.