Several emergency crews responded to a fire at Avon Medical Group, a medical building at 30 West Avon Road in Avon this morning.
Route 167 was closed between Arch and West Main streets as crews responded and smoke was visible from miles away.
The building houses at least 10 doctors' offices as well as a walk-in clinic.
Clinical Lab Partners is directing patients to two other CLP locations in Avon.Patients who have questions about recent tests should call 800-286-9800.
Some medical workers NBC Connecticut spoke with this morning believe they've lost everything and said they are heartbroken.
Fire broke out around 6 a.m. in a lower level and spread, according to officials.
Whether anyone was inside when the fire broke out is not known.
Connecticut Light & Power also responded to the scene.
Firefighters said the damage in significant. They are trying to determine the cause.