Authorities say they now know how a spectacular blaze that tore through an Endicott apartment house started.

Endicott Fire Chief Joseph Griswold at the scene of the March 8 blaze. (Photo: Bob Joseph/WNBF News)

Fire Chief Joseph Griswold said the fire at 1410 Tracy Street was caused by careless smoking. A cigarette that was discarded on a second-floor porch on the back side of the building is believed to have sparked the blaze.

Six adults and eight children from three families were left homeless by the fire, which was reported at 2:11 p.m. Wednesday.

Griswold said the blaze was brought under control after about 90 minutes. No injuries were reported to firefighters or civilians.

The Endicott fire department was assisted by units from other nearby departments.

Griswold said firefighters were on the scene for more than four hours. He said they made regular checks of the house to be sure the fire didn't reignite.

Siding on a house and detached garage north of the burning building at 1412 Tracy Street melted because of the heat from the intense, wind-whipped fire.

Griswold said he believes the three-story structure where the fire originated will have to be torn down because of the extent of the damage.

The upper floors of the building sustained the heaviest fire damage. (Photo: Bob Joseph/WNBF News)

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