The Gilgo Beach killings suspect's wife unknowingly helped in his arrest. She's now filed for divorce

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In her more than 27 years of marriage to Rex Heuermann, Asa Ellerup likely did not know about the gruesome double life her husband is accused of living, Suffolk County's top cop says.

"If you ask me, I don't believe, that they knew about this double life that Mr. Heuermann was living," Suffolk County police commissioner Rodney Harrison said of the suspect's family.

But authorities are not ruling anything out yet and are continuing to collect information "to see if the family might have known exactly what Mr. Heuermann was up to," Harrison told CNN's Erica Hill Monday.

Last week, the 59-year-old Heuermann was arrested and charged with murder in connection to the killings of three of the "Gilgo Four," a group of four women whose remains were found along a short stretch of Long Island's Gilgo Beach in 2010. He is also the prime suspect in the disappearance and killing of the fourth woman but has yet to be charged in that case.

On Wednesday, less than a week since her husband's arrest, Ellerup filed for divorce, her attorney Robert Macedonio told CNN. He did not comment further on the matter.

She was shocked to hear what her husband is accused of, Harrison said.