For more than a decade, investigators remained baffled as 11 bodies were discovered near Long Island beaches as they tried to find a notorious serial killer.

But a new task force started re-examining the mystery less than two years ago, re-interviewed witnesses, studied phone records, and recently arrested a 59-year-old New York City architect in a grisly case that has generated national headlines.

The suspect, Rex Heuermann, has been charged with first-degree murder in the deaths of three women, and police say he is the prime suspect in the slaying of a fourth — Maureen Brainard-Barnes of Norwich.

Barnes disappeared in July 2007 at the age of 25 as a single mother of two children, and her skeletal remains were not discovered until December 2010 near three other women at Long Island’s Gilgo Beach. Her cellphone had pinged on Long Island after her disappearance, but police did not converge on the remote beach area until years later when another woman went missing.

A former blackjack dealer at Foxwoods Resort Casino, Barnes was facing eviction from her apartment at the time of her disappearance and worked as an escort who advertised for clients on Craigslist, police said. That is how she met Heuermann.

A 32-page bail application to keep Heuermann in custody says that Heuermann specifically typed in the name “Maureen Brainard-Barnes” in Google searches as he tried to learn more about his victims and tried to find out what the task force knew about the killings. More than 200 Google searches also included “why hasn’t the Long Island serial killer been caught” as Heuermann searched for documentaries and podcasts about the killings as he was simultaneously trying to outsmart the investigators who were following him. Heuermann, who was tracked down partially by a DNA match on pizza crusts that he threw away in a trash can on the street near his Manhattan office, has pleaded not guilty.

Back in Norwich, friends and family members waited 16 long years between Barnes’ July 2007 disappearance and the arrest as the case took multiple twists and turns that were detailed in a Lifetime movie and in a best-selling book called “Lost Girls: An Unsolved American Mystery.”

Longtime Norwich mayor Peter Nystrom, who represented the city for 18 years in the state legislature before serving for 10 years as mayor, says the community was shaken.

“This was the case that bothered local people here quite a bit, but it is an opportunity to bring closure for the family,” Nystrom said in an interview. “That is a good thing. However, it’s a constant reminder of the horror and sadness of what took place.”

As a state legislator in the 1980s and 1990s, Nystrom worked closely with the families of the victims in the serial killings by Cornell University graduate Michael Ross, a Connecticut native who confessed to eight murders and was executed by lethal injection in 2005. The Gilgo cases were equally difficult on the families, but the long-running mystery has entered a new phase with the arrest.

“You want people to be held accountable, and certainly with something like this, to live all those years without any understanding of what happened or who is responsible — that has to gnaw at you,” Nystrom said.

The story of Barnes dates back to her younger days when she was a straight A student. But she got pregnant at age 16, gave birth at 17, and dropped out of Fitch High School in Groton. She had another baby seven years later and was working as a sex worker when she was last seen leaving a Super 8 motel in midtown Manhattan. Barnes was the first of the known victims to disappear.

In chilling detail, court documents say that Heuermann made “calls checking voicemail on Ms. Brainard-Barnes’ cellphone after her disappearance.” A close friend of Barnes told People magazine that she talked to a man — believed to be Heuermann — and “he described her to a T to me” after meeting Barnes in New York City.

The cases of Barnes and three other women in the “Gilgo Four” had striking similarities, including “the victims appeared to have been placed in close proximity to one another, 22 to 33 feet from the edge of the parkway,” court documents said. “All were petite females approximately 22 to 27 years old, believed to be working as sex workers, all had missing clothing and personal possessions, all had been killed by homicide, all had contact shortly before their disappearances with a person using a ‘burner’ cellphone … without an associated verified identity, and the cellphones of two of the four victims, Brainard-Barnes and [Melissa] Barthelemy, were used by the killer after their deaths. In addition, each of the four victims was found similarly positioned, bound in a similar fashion by either belts or tape, with three of the four victims found wrapped in a burlap-type material.”

The bail application states flatly that Heuermann is “the prime suspect” in the death of Brainard-Barnes in a case that “is expected to be resolved soon.”

Missing in 2007

Starting in 2007, Barnes’ family rallied around the case. Her younger sister, Melissa Cann, reported her missing to the Norwich and New York City police departments. She spent years researching her sister’s case and developing friendships with the families of other victims.

Barnes’ younger brother, William “Will” Vieu, traveled to Manhattan on his motorcycle in an attempt to find his missing sister. He died in August 2009 at the age of 24 in a motorcycle accident on an exit ramp of Interstate 395 in Waterford — more than a year before his sister’s remains were found.

“My brother was destroyed after my sister went missing,” Cann told the Courant in 2012, saying she would not have peace until a suspect was arrested. “He took my sister, he took my life. He took my brother’s life.”

Cann attended the news conference on Long Island with her husband after the arrest, but they declined to comment when asked if any of the victims’ family members wanted to speak. The family has taken a low profile, officials said, since the arrest in the highly publicized case.

The slayings have generated national attention, prompting a convicted and imprisoned serial killer — “BTK Killer’’ Dennis Rader of Kansas — to say that there are such similarities that Heuermann is “a clone” of him.

“I was arrested at age 59. Married, two kids,” Rader wrote in a letter to Fox News Digital. “Husband, dad longtime a serial killer, stalker, used electronic devices, lives in a neighborhood undetected.”

Rader wrote that they were both captured in the same fashion with “DNA and electronics his downfall much like me.”

Why not solved sooner?

Norwich residents and others have wondered why it took more than a decade to solve one of the most high-profile crimes in Long Island history that for years generated a huge number of tips to police.

The answer was that the case was delayed for years as the focus shifted toward a widespread police corruption scandal that led to federal prison sentences for Suffolk County police commissioner James Burke, who oversaw nearly 2,300 officers, and longtime Suffolk County district attorney Thomas J. Spota. Burke was sentenced in 2016 to nearly four years in prison, and Spota was sentenced to five years and disbarred as an attorney after being convicted of witness tampering, conspiracy to tamper with witnesses, and obstruction of justice during the investigation into the police commissioner. Christopher McPartland, the former leader of the anti-corruption bureau in the prosecutor’s office, was also sentenced to five years in prison in the scandal. Both Spota and McPartland were close personal friends of Burke — and all three were highly powerful in Suffolk County due to their positions.

The police commissioner and top prosecutor both refused for years to allow the FBI to help police in the unsolved Gilgo Beach killings, and the FBI then investigated Burke for more than two years before arresting him in an unrelated case that led to his prison sentence. Burke had been charged with conspiring to obstruct justice after beating a handcuffed heroin addict inside the police precinct because the addict had stolen a duffel bag from Burke’s police vehicle that contained sex toys, pornography and Viagra.

Federal prosecutors charged that Burke had “severely undermined the public’s trust in law enforcement at a time in which relations between law enforcement and the public are at an all-time low.”

After the scandals subsided, an entire new law enforcement team was installed, and a new set of investigators started looking into the Gilgo killings. Less than 18 months later, Heuermann was arrested.

Norwich reaction

The Norwich police department initially investigated the matter as a missing person case, but they largely handed the report to the New York City police department after it was determined that Barnes had traveled by Amtrak train from New London to Manhattan.

Norwich police chief Patrick Daley was serving in the department when Barnes went missing and has been following the case for the past 16 years, including the past seven years as chief.

“I was here when that case happened in 2007,” Daley said. “We investigated it for a while, but then once it was confirmed that her last area was in New York City, we consulted with the New York City missing persons unit and then we eventually turned the case over to them. We did go down for investigatory interviews down there [in Manhattan], and we were able to confirm that she was there. After the body was discovered, we assisted Suffolk County. We have been in contact with them over the years.”

While Heuermann has not been charged with the Barnes arrest, Norwich residents are breathing a sigh of relief.

“I’m glad that Suffolk County was able to take him off the streets,” Daley said. “It was a tough case. If you watched that press conference where they laid out all the steps they did, it’s an impressive amount of police work. … There’s a sense of closure for the police department and the city — just to know and to get some justice.”

The investigation required a massive amount of law enforcement work, including more than 300 subpoenas and search warrants that included records from Google, Verizon, T-Mobile, and American Express, among others.

State Rep. Doug Dubitsky, a Republican attorney who represents part of Norwich in the state legislature, said he is hoping that the arrest in several cases will bring solace to the family after 16 years.

“When someone goes missing — for the rest of your life, you think about what happened, where are they, who did this and why,” Dubitsky said. “Maybe it will bring a little closure to the family.”

Former state Rep. Steven Mikutel, a law-and-order Democrat who was born and raised in Norwich, said he had been hoping for an earlier arrest. He was serving as a state legislator when Brainard-Barnes disappeared and when her remains were found.

“It took them too long to put all the pieces together,” Mikutel said. “Serial killers tend to be smart people, and they get away with their crimes because they can cover their tracks. He was monitoring the cops who were monitoring him. If I was a state rep, I would call for the immediate execution of all serial killers. The death penalty is effective if it’s allowed to work.”

Mikutel added, “I’m just glad that one less serial killer is on the streets. No matter who was his victim, they didn’t deserve to be murdered by this creep.”