SOUTHWICK (AP) — Massachusetts officials say a fire at a home where a mother rescued her toddler son early Christmas morning was an accident, but they weren’t able to determine the cause.

The state Department of Fire Services announced Friday that the fire in Southwick started in the living room of a basement apartment near a Christmas tree and a couch.

Investigators say they ruled out the electrical circuit that fed lights on the tree as the origin, but couldn’t eliminate the tree lights or other potential causes because of extensive fire damage.

A Christmas Eve fire in Southwick (Photo credit WSHM)

A Christmas Eve fire in Southwick (Photo credit WSHM)

Officials say the mother, Hanna Turner, couldn’t rescue her son while inside the house, so she smashed an outside window, crawled inside and pulled him out.

Firefighters say the mother and boy were injured but are expected to recover.

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