A Sheffield man is believed to have killed his wife and three children Wednesday before setting their house on fire and committing suicide, the Berkshire District Attorney said Thursday.
The Berkshire Eagle  reports Luke Karpinski apparently killed Justine Wilbur and their children — 7-year-old twins Alex and Zoe, and Marek, 3, according to District Attorney Andrea Harrington. He then set their Home Road house on fire before killing himself.
Harrington did not disclose a weapon used in the killings or the causes of death. Nor would Harrington say whether the victims were dead before the fire started or how it was set.
Meanwhile, state and local authorities continued their investigation Thursday into the deaths. The state fire marshal and other authorities were at the scene on Home Road, and by late morning the road was blocked off to nonresidents. Police said it would remain closed for the rest of the day.
Shock rippled through the small, rural community of about 3,000 people, including at Undermountain Elementary School, which two of the children attended.
The couple, graduates of Wahconah Regional High School, had moved back to Massachusetts from Virginia, where they worked in the patent industry. Luke Karpinski was a federal chemical patent examiner who worked from home, Kristen Wilbur said.
A statement from the law firm where Justine Wilbur worked says her colleagues are facing "grief and immeasurable sorrow."

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