The US Federal Communications Commission (FCC) has said that it will look into an AT&T outage that left customers unable to access 911 emergency services on Wednesday (8 March). AT&T's 911 outage reportedly began late Wednesday and lasted for around an hour. FCC chairman Ajit Pai announced on Twitter that the department's safety staff would investigate the matter.

Pai claimed that he spoke to AT&T CEO Randall Stephenson about the issue."Every call to 911 must go through," Pai said in a statement, Reuters reported. "I have directed commission staff to track down the root cause of this outage."

AT&T spokesperson Mike Balmoris said the firm takes its 911 obligations very seriously. "We are taking steps to prevent this from happening again and will be sharing additional information with the FCC," he added.

During the outage, several law enforcement agencies and fire departments across the US took to Twitter to report about the 911 outage and urged affected users to communicate with them using alternative means, such as calling in through the mainline non-emergency numbers.

However, as pointed out by the Arlington fire department in a tweet, mainline phone calls do not show callers' location and such callers were thus required to specify their address, likely affecting response time during emergency situations.

The outage is believed to have affected customers in at least 14 US states including Alabama, Arkansas, California, Colorado, Florida, Indiana, Kentucky, Louisiana, Maryland, Pennsylvania, Tennessee, Texas, Virginia, West Virginia and Washington, the New York Times reported.

However, it still remains unclear as to how many users were affected by the outage, whether it was a nationwide issue and what caused it. AT&T has since claimed that the issue has been resolved and apologised to affected customers.