T-Mobile announced overnight that customers should be back up and running again after a nationwide outage of its voice and data network that also jammed up every other major carrier’s service.

Just after 1 a.m. Tuesday, the company’s president of technology, Neville Ray, tweeted: “Voice and text services are now restored. Thank you for your patience as we fixed the issues. We sincerely apologize for any and all inconveniences.”

There were no initial reports of hacking, a cyberattack or other foul play.

However, the Federal Trade Commission, which is responsible for the enforcement of civil U.S. antitrust laws and the promotion of consumer protection, planned to open an investigation, according to The Wall Street Journal.

The company issued an official statement about the matter on its website, and called the problem an "IP traffic related issue."

IP means internet protocol, and is a unique address that identifies every device connected to the Internet.

All the major wireless carriers throughout the United States reported the widespread outages Monday that disrupted communications for hours, according to multiple reports.

T-Mobile, Sprint and Verizon customers all reported massive service disruptions in multiple states. AT&T’s service was also interrupted due to the issue but has since returned to “operating normally,” the company said, noting that it was still possible that some customers would be unable to reach people on other carrier networks.

Verizon also reported it was “performing well” now.

About 6 p.m., T-Mobile reported its data services were available again and that some calls were completing.

Sprint had not yet responded to requests for comments.

The multi-network outage originated at T-Mobile, according to a report by The Verge, and then about an hour later spread to text messages, and incoming and outgoing calls of the other carriers.

People were mostly reporting dropped calls.

Reports about the outage began spiking about 2:20 p.m. local time.

According to the online cellular service tracker Down Detector, 92% of cell customers reported problems with their phone Monday.

Just after 3 p.m., there were more than 93,000 reports of T-Mobile outages and varying reports from the other carriers, according to Business Insider.

A map released by T-Mobile showed hot spots for outages that stretched from Seattle to Florida. Atlanta appeared to be one of the areas most affected.

Service in nearly every major metropolitan area of the country was hit.

Los Angeles, San Francisco, Dallas, Houston, Minneapolis, Chicago, St. Louis, Detroit, New York, Boston, Washington and all of South Florida were among the most notable cities highlighted in red.

In Mesa, Arizona, 30,000 mobile customers were reported without service.

“Our engineers are working to resolve a voice and data issue that has been affecting customers around the country. We’re sorry for the inconvenience and hope to have this fixed shortly,” Neville Ray, T-Mobile’s president of technology, said earlier on Twitter.

Verizon said its network had begun performing well again, but said it was aware of T-Mobile’s network issues and said calls to and from T-Mobile customers might receive an error message.