WASHINGTON (AP) — Verizon says 911 service has been mostly restored in northern Virginia after being knocked out by Friday night’s storm.

The storm known as a derecho knocked out power to a Verizon facility in Arlington that resulted in 911 calls not working in Fairfax and Prince William counties and the city of Manassas.

Verizon spokesman Harry Mitchell says 911 calls are going through again in those jurisdictions. In Fairfax, however, operators still aren’t seeing the addresses of people who call. He says the storm was a “historic event” that knocked out both primary and backup power to the 911 routing facility.

Fairfax County Board of Supervisors Chairman Sharon Bulova says 911 service in the county was disrupted for an “unacceptable” period of time.

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