AT&T says its cellphone network restored after a widespread outage hit users across the US

AT&T said Thursday its wireless network was back after an outage knocked out cellphone service for its users across the U.S. for hours.

“We have restored wireless service to all our affected customers,” the Dallas-based company said in a statement posted on its website Thursday afternoon. “We sincerely apologize to them.”

Outage tracker Downdetector noted that outages, which began at about 3:30 a.m. ET, peaked at around 73,000 reported incidents. AT&T had more than 58,000 outages around noon ET, in locations including Houston, Atlanta and Chicago. The carrier is the country’s largest, with more than 240 million subscribers.

By 5 p.m. ET, the reports were down to about 1,200.

Cricket Wireless, which is owned by AT&T, had more than 9,000 outages at one point but the reports had also tailed off later in the afternoon. Users of other carriers, including Verizon and T-Mobile, also reported issues but those companies said their networks were operating normally and the problems were likely stemming from customers trying to connect to AT&T users.

Some iPhone users saw SOS messages displayed in the status bar on their cellphones. The message indicates that the device is having trouble connecting to their cellular provider’s network, but it can make emergency calls through other carrier networks, according to Apple Support.

So far, no reason has been given for the outages.