No pets were in the Animal Hospital of Fairifeld when a destructive fire broke out Saturday night, responders said.
Staff made it out before the three-alarm blaze tore through the Fairfield Road building, which isn't a boarding facility.
The fire broke out shortly after 9 p.m. and immediately went to two alarms, the Fairfield Volunteer Fire Department said.
Flames blew through the roof as firefighters conducted a "surround and drown," the department said.
The scene was cleared at 11:50 p.m.
Colleagues from Cedar Grove, Lincoln Park, Bloomfield, North Caldwell, West Caldwell, Pine Brook and Verona were among the mutual aid responders.
Authorities were trying to determine the cause.
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