The 20-year-old son who was the sole survivor of a fire in Carmel, N.Y., that killed his parents and sisters was questioned by detectives for 3 1/2 hours, officials said Thursday.
Investigators have not labeled Tuesday's fire suspicious, but have not ruled out foul play.
"We're not saying it was arson," Carmel Police Chief Michael Johnson said. "We're not saying it wasn't arson."
In an emailed update, he said Thomas Sullivan Jr. "was able to provide additional details of what occurred that night."
Thomas Sullivan Sr., a Larchmont police captain, his wife, Donna, and their daughters, 18-year-old Meaghan and 13-year-old Mairead, died early Tuesday in the blaze.
The police chief said the son provided information in the interview "that law and fire personnel needed to know in order to proceed with the investigation."
The chief said he's awaiting results from the state police laboratory on samples taken from the scene. Neighbors, emergency responders and others are still being interviewed, he added.
The chief gave no further details and said that "out of respect for Tom Jr. and the relatives of the Sullivan family" his department would not comment further until after Saturday's funeral.
Hundreds of people gathered Thursday for a wake at a funeral home, where four urns containing the family's remains were on display.
Thomas Sullivan Jr. was not present at the start of the wake. Putnam County Executive Mary Ellen Odell, a family friend, said he was with his grandparents.
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