A law enforcement task force will continue to work "full time" to gather evidence after a suspect has been charged in some of the Gilgo Beach killings, including further investigation into a string of other human remains found scattered across Long Island more than a decade ago, a top investigator told CNN.

"I don't think any of us know what exactly is going to turn up, but we're going to continue the investigation," Suffolk County Deputy Police Commissioner Anthony Carter told CNN on Sunday.

Rex Heuermann, 59, was arrested Thursday and charged with the murder of three of the "Gilgo Four," a group of four women whose remains were unearthed near the island's Gilgo Beach in 2010. He has pleaded not guilty to the killings of Melissa Barthelemy, Megan Waterman and Amber Costello.

He is also the prime suspect in the 2007 disappearance and killing of the fourth woman, Maureen Brainard-Barnes, according to a bail application from prosecutors, though he has yet to be charged in the case.

The Gilgo Four are among 11 sets of human remains that were found strewn across Long Island's South Shore between 2010 and 2011, launching what police have called "one of the most consequential homicide investigations" in the island's history.

Heuermann has so far only been charged in connection to three of the killings.

When asked whether investigators expect to connect Heuermann to more victims, Carter said, "As we continue to gather evidence, anything is possible."

The multijurisdictional task force will continue to investigate Heuermann and the remaining unsolved cases by piecing together years of the suspect's activities, combing through tip lines and and interviewing witnesses, Carter said.

"There's still an active investigation as to his whereabouts and his conduct from the time that the bodies were discovered right up until Thursday," the investigator said.

Authorities have had Heuermann on their radar for more than a year as investigators gathered enough evidence to make an arrest. But they ultimately decided to arrest him Thursday out of concern that he may have set his sights on another victim, Carter said.

"It was an adrenaline rush," he said of hearing the arrest was finally happening.

"I knew that this person was a demon," Carter said. "The fact that we are able to bring some closure and some peace to the families as well as take a violent person off of the streets is rewarding, I think, for everyone."

Here's what we know about the investigation into the suspect.

Authorities lay out key evidence

The case began in 2010 when the search for a missing woman led to the unexpected discovery of the Gilgo Four -- who were found bound in camouflaged burlap along the same quarter mile stretch of roadway.

By the time authorities ultimately found the remains of the missing woman, Shannan Gilbert, a year later, they had uncovered a total of 11 sets of remains along Long Beach's South Shore -- all within miles of Gilgo Beach.

After the cases went unsolved for more than a decade, until a multi-agency investigative task force was formed in early 2022 to revisit the cases.

Within weeks, the task force identified Heuermann as a possible suspect, according to Suffolk County District Attorney Ray Tierney. Investigators then began to surveil him and his family, surreptitiously collected DNA samples and analyzed his phone records for any connection to the killings.

Ultimately, investigators connected Heuermann to at least three of the killings using in part DNA evidence, phone records and credit card bills, authorities have said.

Authorities narrowed thousands of cell tower records down to a handful of people and then began focusing on residents who also matched a physical description provided by a witness who had seen the suspected killer.

Heuermann matched the witness's description, lived close to the Long Island cell site and worked near the New York City cell sites where other calls were captured, authorities said.

A key break in the case came when investigators were able to match DNA from a piece of male hair found on the burlap used to wrap Waterman's body to a DNA sample taken from a pizza crust Heuermann had discarded in a Manhattan trash can in January.

Additionally, a search of the suspect's computer unveiled a harrowing search history that included at least 200 internet searches for information about the status of the Gilgo investigation, as well as compulsive searches for photos of the victims and their families, Tierney said.

The records also included searches for violent pornography and depictions of women being abused, raped and killed, the prosecutor said.

Heuermann's wife and two children were out of state during the times the three women were believed to be killed, Tsoierney said.

The suspect's wife and children are cooperating with the investigation, according to Carter.

Investigator describes suspect's alleged acts as 'worst case I've ever seen'

Carter, the deputy police commissioner, told CNN that Heuermann's alleged actions are among the most disturbing cases he has seen in his career.

"I can't begin to imagine the pain that these families have had to endure over the last decade and to know that this demon was capable of doing such an evil act to these families, it is just, you know, beyond comprehension," Carter said.

The police commissioner repeatedly described Heuermann as a "demon."

"It's really hard to get into the mind of somebody that's capable of committing the crimes that he committed," Carter said. "He intended to commit these crimes. He intended to cover up these crimes, and the acts that he committed were the worst I've ever seen," he said.

Heuermann lived in the village of Massapequa Park with his family -- just across the bay from where the victims' remains were found.

The suspect, who is a registered architect, has owned the New York City-based architecture and consulting firm, RH Consultants & Associates, since 1994, according to his company's website.

The investigation is far from over

Despite Heuermann's arrest in connection to three of the Gilgo Beach homicides, the cases of several other human remains uncovered in the area around the same time are still unsolved.

Though prosecutors have said in court documents that Heuermann is also the "prime suspect" in the killing of Brainard-Barnes, the last of the Gilgo Four, no charges have been made in the case. The investigation is "expected to be resolved soon," according to prosecutors' bail application.

After the remains of the Gilgo Four were uncovered, seven more sets of remains were found along the coast, including the partial remains of a woman later identified as Jessica Taylor, a female toddler and the toddler's mother, according to police.

The last remains to be found were those of Shannan Gilbert -- the woman whose disappearance led investigators to find the Gilgo Four and set off the string of subsequent discoveries. Authorities later said they believed Gilbert's death may have been accidental and unrelated to the Gilgo Beach homicides.

"We're going to continue to work this case and work the entire Gilgo investigation," Carter said.

"The detectives in this case -- one thing I really want to say about them -- they never quit," Carter said. "They've been working this case for over a decade and they never quit."