Massachusetts can again make 911 phone calls after the system went down for over an hour across the state Tuesday, officials said.
It wasn't immediately clear what caused the outage, which lasted over an hour. It even affected the announcement of details on the Boston Celtics' championship parade.
"Thank you for your patience + cooperation," the state's Executive Office of Public Safety and Security said, saying the investigation remained ongoing.
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Amid the outage, public safety alerts rang out across phones in Massachusetts — and accidentally in nearby states, according to the emergency management agencies in Maine, New Hampshire and Connecticut; the former said the Federal Emergency Management Association was investigating.
The New Hampshire Department of Safety’s Division of Emergency Services and Communications said in a statement it was "aware of some New Hampshire cell phone users receiving a notification about a statewide outage," and that the notification only applied to Massachusetts — "New Hampshire 911 remains fully operational."
The end of the outage was reported about 3:43 p.m.
Earlier, Massachusetts' Executive Office of Public Safety and Security had said the State 911 Department was investigating the disruption to the phone system and urged residents to call their local police department directly.
State police also noted the outage, referring callers who need help to regional dispatch centers.
Police in Boston, Worcester, Medford and Malden and fire departments in Brockton and Hanson were among the first to share information on the outage. The agencies urged people who need help to call the local number for their department.
"9-11 is currently down statewide," Boston police said in a statement. "If you are experiencing an emergency please pull a Fire Box."
Boston Mayor Michelle Wu mentioned the outage at the start of her Boston Celtics NBA Championship parade news conference Tuesday afternoon, saying, "We've been in touch with the state and all the relevant officials to work on getting this resolved."
The State 911 Department, which oversees the system, hasn't put out a statement on its social media pages about the outage. NBC10 Boston reached out for more information.
During a national AT&T phone network outage in February, Massachusetts State Police urged the public not to call 911 just to see if it works.