- Written by James Fitzgerald
- bbc news
People in four U.S. states were unable to make 911 calls Wednesday night after widespread problems with the system.
Call centers in Nevada, Nebraska, South Dakota and Texas reported outages, but many services have now been restored.
Federal officials have previously warned that emergency services' transition to digital systems comes with the risk of cyberattacks.
However, the cause of last night's problem has not yet been revealed.
In Las Vegas, Nevada, problems were reported for several hours, and police said service had been restored just after 10 p.m. local time (4 p.m. Japan time).
Police previously said they were able to see the emergency call coming from the mobile device and were able to call the caller back.
But they appealed to the city's hundreds of thousands of residents not to ring in order to test their connections.
The Rapid City, South Dakota, Police Department echoed this sentiment, announcing just before 9 p.m. local time that local police were being “inundated” with calls trying to confirm whether the lines were working.
Officials said the problem is playing out “state-wide,” but said text messaging functionality will remain available for people to contact in an emergency.
Meanwhile, local units across Nebraska took to their Facebook pages to provide callers with alternative numbers to call and later updated that they too were back online.
Police in Del Rio, Texas, said the problem was isolated to one cell phone company and insisted there were no problems with its calling system or emergency services themselves.
Federal officials have not yet commented on the incident.
The National 911 Program has previously highlighted the benefits of digitizing emergency services across the country, but warned that this comes with an “increased risk of cyber security attacks”.
One such attack in 2017 shut down 911 centers in more than a dozen states, according to Reuters.