New York investigating AT&T over nationwide outage that left 70,000 without service - and urges residents to file complaints

New York is opening an investigation into the cause of the massive AT&T cellular outage that left thousands of Americans without service last week.

Attorney General Letitia James announced the probe Thursday, noting nationwide outages are dangerous and especially the one on February 22, which prevented calls, text messages or internet access for up to 12 hours.

AT&T blamed issues on a 'software glitch' and told customers who were impacted that they would receive a $5 credit to their next bill.

James has also urged all New Yorkers who were impacted to file a complaint with her office.

The Federal Federal Bureau of Investigation (FBI) and Department of Homeland Security (DHS) had opened an investigation the day cellular service went down.

New York is opening an investigation into the cause of the massive AT&T cellular outage that left thousands of Americans without service last week

'Americans rely on cell service providers for consistent and reliable service to help them with nearly every aspect of their daily lives,' said James.

'Nationwide outages are not just an inconvenience, they can be dangerous, and it's critical that we protect consumers when an outage occurs. 

'I encourage any New Yorker who was affected by this disruption to file a complaint with my office.'

The outage was first reported in the early hours of Thursday morning when customers were unable to make emergency calls, with multiple 911 centers reporting that users were unable to connect.

Smartphones were stuck in 'SOS' mode.

There were reports that other networks were affected, but this is thought to have been the result of failed attempts to place calls to AT&T numbers.

Cyber experts told DailyMail.com the issue had hallmarks of a cyberattack, potentially an attempt by hackers to blackmail the company or steal user data.

The outage was first reported in the early hours of Thursday morning when customers were unable to make emergency calls, with multiple 911 centers reporting that users were unable to connect. Smartphones were stuck in 'SOS' mode

James has also urged all New Yorkers who were impacted to file a complaint with her office. Pictured are AT&T customers lining up at a store last week hoping to get answers 

The widespread nature, according to experts, seemed similar to 'a massive Distributed Denial of Services (DDOS) attack on core Internet infrastructure.'

Using DDOS, cybercriminals are attempting to crash a website or online service by bombarding it with a torrent of superfluous requests at exactly the same time.

READ MORE: Pro-Russian hackers claim THEY were responsible for AT&T outage

A screenshot attached to the X post showed that someone had shared telecommunication outage data on the social media app Discord, using it to claim responsibility for the People Liberation Front. 

The surge of simple requests overload the servers, causing them to become overwhelmed and shut down.

DDOS was deployed in 2016 when it knocked out major sites like Netflix, Twitter, Amazon and PayPal for hours.

But the U.S. Cybersecurity and Infrastructure Security Agency (CISA) reported that 'the cause of the outage is unknown and there are no indications of malicious activity.'

Still, National Security Communications Advisor John Kirby told reporters Thursday afternoon that DHS and the FBI were looking into the outage as well and working with the tech industry and network providers to see what can be done 'from a federal perspective to enhance their investigative efforts to figure out what happened here.' 

On Friday, a pro-Russian hacktivist group had claimed responsibility for the AT&T outages that left many customers' phones stuck on 'SOS mode.'

Goups 62IX, the People Liberation Front, and Anonymous Legion claimed responsibility for the incident.

These groups, which a cybersecurity expert criticized as being pro-Russian, have also claimed responsibility for other US telecommunications outages.

But the claim is false, claimed cybersecurity and hacktivism expert who goes by the alias 'CyberKnow' in a post on X.

It's an example of what the writer called 'post-event victim claiming', designed to sew confusion and bolster their reputations.