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.

But she unknowingly played a key role in her husband's arrest: it was her DNA, among other evidence, that authorities say helped tie Heuermann to the crimes.

Here's what we know about his wife, their life together and the unexpected role she played in the case.

The two have been married for 27 years

Heuermann and Ellerup were married in April 1996, the suspect said in a 2018 deposition. Since then, they lived in Heuermann's red and green childhood home in the Long Island suburb of Massapequa Park with their daughter and Heuermann's stepson.

But despite their long stint in the neighborhood -- and though Heuermann's life was long rooted in the same community, neighbors knew little detail about the family.

Neighbors described the home as creepy and the family as distant, according to the Long Island Press, a monthly magazine serving Long Island.

"The family is very to themselves, quiet," neighbor Frankie Musto told the publication. "We never saw anything suspicious."

In his 2018 deposition, Heuermann said he had been married once before. That marriage, he said, lasted three years and they had no children.

Wife's hair found with all three victims

When the victims were first discovered, there were pieces of degraded hair recovered by authorities -- but DNA testing at the time could not provide the answers investigators hoped for.

Technological improvements soon helped yield results.

Hair that is now believed to belong to Ellerup -- which presumably had been unintentionally carried by the suspect on his clothes -- was found on or near the three victims, prosecutors alleged in the bail application, citing DNA testing.

That DNA came from 11 bottles inside a garbage can outside the Heuermann home, the court document says. Authorities had been surveilling Heuermann and his family for months after they identified him as a suspect in early 2022, and during that time collected DNA samples from items the family threw away.

Though her hair was found with the victims, Ellerup and their daughter were both traveling when the killings were committed and Heuermann was "alone in the tri-state area," Suffolk County District Attorney Ray Tierney said during a Friday news conference.

"It's very significant in as much as it then limits it down to him," criminal defense attorney Joey Jackson told CNN's Jake Tapper about the finding. "If the suspect's wife is out of town, then why would her hair be there if he's in town?"

Suffolk County authorities say DNA evidence also linked Heuermann to a male hair found on the burlap sack where one victim's remains were found.

Shocked, disgusted, embarrassed

Harrison told CNN on Monday he was informed that once authorities told Ellerup and her daughter about the crimes Heuermann is accused of, the two were "shocked, they were disgusted, they were embarrassed."

Their reaction, he said, is why he believes they were not aware of what he was doing.

"But, time will tell," he added. "And once again, there are still a lot more questions that need to be done to the family and friends."

CNN has made multiple attempts to contact Heuermann's wife and daughter.

Following his arrest, Heuermann was remanded without bail. He entered a not guilty plea through his attorney. His next court date is scheduled for August 1.

Heuermann has had no visitors in the Suffolk County correctional facility where he's being held since his Friday arraignment, Suffolk County Sheriff Errol D. Toulon, Jr., told CNN's Brynn Gingras. He is allowed to make two phone calls daily but it's unclear if he has connected with anyone, the sheriff added.