AT&T’s network suffered widespread outages across the country Thursday morning with cellular service and internet down, according to the tracking site Downdetector.

Other cellular providers, including Verizon, T-Mobile and Cricket Wireless, have also reported outages. Verizon and T-Mobile said those affected had been trying to contact AT&T users.

About 75% of AT&T network services have been restored as the number of outages across different carriers steadily declined throughout the day.

It’s remains unclear what triggered the service disruption.

AT&T acknowledged the issue Thursday morning, saying: “Some of our customers are experiencing wireless service interruptions this morning.”

The company has since made progress in restoring service.

“Our network teams took immediate action and so far three-quarters of our network has been restored,” AT&T said in a statement. “We are working as quickly as possible to restore service to remaining customers.”

Cricket Wireless, which is owned by AT&T and uses its network, is also experiencing cellular problems.

Verizon said Thursday morning that the outages are not affecting its network directly, only customers trying to reach another carrier.

T-Mobile also said early Thursday that the network didn’t suffer an outage and is operating normally, and Downdetector numbers likely reflect customers attempting to reach users on other networks.

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