NEW YORK (CBSNewYork) – We now know what caused sewage to flood several homes over Thanksgiving weekend in Queens.

The New York City Department of Environmental Protection says a collapsed sewer pipe is to blame for the backup that spewed filth into more than 100 houses.

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Investigators originally thought it was from grease being poured down the drain.

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The DEP says city officials will now start evaluating claims for property damage.