WASHINGTON (AP) — A cyberattack caused a nearly daylong outage of the nation’s new 988 mental health helpline late last year, federal officials told The Associated Press Friday. Lawmakers are now calling for the federal agency that oversees the program to prevent future attacks.

“On December 1, the voice calling functionality of the 988 Lifeline was rendered unavailable as a result of a cybersecurity incident,” Danielle Bennett, a spokeswoman for the Substance Abuse and Mental Health Services Administration, said in an email.

The attack occurred on the network for Intrado, the company that provides telecommunications services for the helpline. The agency did not disclose details about who it believes launched the attack or what kind of cyberattack occurred. Intrado is working with a third-party assessor to investigate the incident and law enforcement agencies have been notified of the breach, SAMHSA said.

The national 988 phone number, which can be reached by text, chat or voice calling, has become a lifeline for millions of Americans seeking help during a mental crisis, with millions of calls pouring in during the first six months since its launch in July. The system is designed to work similarly to 911 — it’s a universal, easy-to-remember number that people can call in an emergency to reach a human who is working around the clock in a local call center.

Those who tried on Dec. 1 to reach the line for help with suicidal or depressive thoughts were instead greeted with a message that said the line is “experiencing a service outage.” Text and chat services, however, remained available to those who needed help.

The Federal Communications Commission said in December it was investigating the outage. Intrado said at the time that the company was “experiencing an incident that is impacting production across numerous systems” and is “working diligently to restore service.” Intrado could not immediately be reached for comment Friday.

Last week, Democrat Rep. Tony Cárdenas and Republican Rep. Jay Obernolte, both of California, introduced a bill calling for better coordination and reporting around cyberattacks on the 988 system.

“Even a few hours’ outage of the national suicide hotline can cost American lives,” Obernolte said in a press release introducing the bill. “It’s critical that we mitigate the risks of future disruptions to the service and take steps to resolve cybersecurity vulnerabilities that could put the hotline at risk.”

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