The Harris County Fire Marshal's Office shared photos of the aftermath of the blaze, which was reported just before 7 p.m. on Sunday along Aldine Mail Route, east of Airline.
Investigators said an unattended burn barrel close to the building likely sparked the fire, which had been burning for a while behind the funeral home.
A spokesperson told ABC13 someone was burning their trash in the burn barrel since Friday, but the fire never went out, smoldering.
According to the fire marshal, the remains of three people were in the funeral home at the time and were taken to another facility. No one was hurt in the fire.
HCFMO said the fire was determined to be accidental, adding that there was a partial collapse of the building.
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