Several US mobile carriers experienced technical difficulties Monday night.

DownDetector, a website that tracks service problems and outages, indicated that AT&T, T-Mobile, Verizon and Boost Mobile all experienced a spike in reports Monday night.

It was unclear if the problems were connected.

Neville Ray, president of technology for T-Mobile, tweeted late Monday that the company was “addressing a 3rd party fiber interruption issue that has intermittently impacted some voice, messaging and data services in several areas.”

Ray later tweeted that T-Mobile had “seen significant improvement and [is] operating at near normal levels.”

It was unclear which geographical areas were affected by the issues.

AT&T, Verizon and Boost Mobile could not be immediately reached for comment.

Posts on and indicated T-Mobile service outages in multiple areas of the country. Many Twitter users also reported outages.

Posted comments on the site came from users who said they were located in Arizona, California, Colorado, Florida, Hawaii, Kansas, Nebraska, North Carolina, Oklahoma, Texas and Washington.

Numerous posts by users said their service had been changed to “SOS mode,” meaning they were not directly connected to a network but could still make emergency calls.

The outage is the third major network problem reported over the last month, including outages hitting Twitter and Microsoft Teams. provided a chart tracking service complaints within the previous 24 hours indicating a peak of more than 69,000 reported outages in a two-hour period.

Similar service complaints on originated from some of the same states, as well as Alabama, Connecticut, Idaho, Minnesota, New York, Nevada, South Carolina and others.

Many posts reported service eventually was restored.

Microsoft: Teams, Outlook, other services hit by outage are now ‘stable’