Jasmine Robinson sat in a Suffolk County courthouse Friday, listening intently as prosecutors explained how they had tracked a man they suspected of killing and burying at least three women on Long Island’s South Shore. She heard how they had used DNA painstakingly harvested from his pizza crusts, triangulated his mobile phone signals and spent hours on old-school, shoe-leather stakeouts.
She did not hear who might have killed her cousin, whose head and hands were also found near remote Gilgo Beach.
A Massapequa Park architect, Rex Heuermann, pleaded not guilty last week after he was charged in three killings of women whose bodies were found on the barrier island. Authorities have said he is the prime suspect in a fourth. But in total, 11 bodies were discovered.
For Ms. Robinson, the hearing and the aggressive investigative techniques were a sign that the police might finally solve the killing of her cousin, Jessica Taylor. Days after Ms. Taylor went missing in New York in July 2003, a woman walking her dog found the victim’s torso in the woods in Manorville, about 45 miles east of Gilgo Beach, but almost eight years went by before the rest of her remains were discovered at Gilgo.
The hearing bolstered her confidence, Ms. Robinson said.
“I’ve had hope forever, and every morning I wake up, it’s like, ‘Maybe this is the day,’ ” Ms. Robinson said in an interview on Saturday. “Hearing everything yesterday, it proves that they’re working, and they’re working hard. I’m excited to see what comes next.”
Since the police announced an arrest in the 12-year investigation on Friday, the focus has been on the cases of the four women whom investigators have so far connected to Mr. Heuermann. For the relatives of the other victims found along the beach, the news was a stinging reminder that they were still awaiting answers.
The families have watched for more than a decade as the investigation was hamstrung by dysfunction and mired in corruption. Then, last year, investigators joined with state and federal agencies to re-examine the case.
“The task force is continuing the investigation into the other deaths,” was all that the Suffolk County Police Department would say Tuesday. A spokeswoman for the county district attorney’s office said it would not discuss a continuing investigation.
For some of the victims’ families, last week’s arrest was a reason to keep the faith. For others, it merely amplified their frustration.
Investigators began to focus on Gilgo Beach in 2010, when Shannan Gilbert, who had answered a call for an escort in the area, disappeared. Investigators soon discovered the first four buried bodies. Ms. Gilbert’s remains were found a year later, in Oak Beach marshlands about six miles from Gilgo Beach. Though the police have suggested that her death was not a homicide, her family disagrees and knows little about how and why she died.
“I am so happy for the four that are able to get those answers,” said Sherre Gilbert, her sister, adding: “I feel like they could have done this years ago had they brought the right people in.”
The investigation began in earnest in December 2010 when a Suffolk County officer, John Malia, and his K9 partner, Blue, were searching a stretch of Ocean Parkway near where authorities believed Ms. Gilbert had gone missing, according to prosecutors. Blue discovered human remains.
The police later determined that they did not belong to Ms. Gilbert, but to Melissa Barthelemy, a 24-year-old woman from the Bronx who had worked as a prostitute until she disappeared in July 2009. When the police returned two days later, they found the remains of three other women — Amber Lynn Costello, Megan Waterman and Maureen Brainard-Barnes.
All four were petite, in their 20s and had worked as prostitutes. They were all also found bound at the feet or ankles and wrapped in burlap along a stretch of sand about a quarter mile long.
Seven other bodies would be found in the months that followed, including Ms. Gilbert, four other women, a man who was never identified and a 2-year-old girl. The bodies, two of which were only partial remains, had not been bound and wrapped as those in the first group were.
Numerous killers have sometimes disposed of bodies in a single location — parts of Brooklyn and New Jersey swamps, said Fred Klein, a lawyer and the former Nassau County assistant district attorney who prosecuted the serial killer Joel Rifkin. But that dumping, he said, has generally been the work of an organized crime group or gang.
“The unusual part would be for random people to be using the same location,” said Mr. Klein, who is now an assistant law professor at Hofstra University. “It almost stretches the imagination to believe more than one different person, completely dissociated with each other, just coincidentally happened to dump dead sex workers in the same location.”
But the search area ultimately stretched for miles, and Joseph Giacalone, an adjunct professor at John Jay College of Criminal Justice who ran the Police Department’s Bronx cold case squad, said a broad search can unearth unexpected discoveries: “When you have these vast wooded areas, it depends on how far the police department wants to go and how many bodies they want to find.”
When investigators launched the task force last year, they concentrated on the first four women found, said District Attorney Raymond A. Tierney in an interview with ABC’s “Good Morning America.”
“Those murders: The patterns are very similar,” he told the host. “That’s what this grand jury investigation was all about. We’re going to work through this case, and then we’re going to continue to investigate all those other bodies as well.”
Mr. Heuermann’s arrest could also be significant in helping investigators solve the other victims’ cases, said Mr. Klein. In the past, witnesses’ memories have been jogged after seeing a news segment or reading about an arrest, he said.
Since Friday, officials in Suffolk County have executed warrants, seizing evidence from Mr. Heuermann’s home and a storage unit, including more than 200 guns.
But as officials continue their investigations, Ms. Gilbert said that the task of solving her sister’s death now lies primarily with her and her lawyer.
Last year, the police concluded her sister’s cause of death was undetermined but probably accidental, with substance abuse and mental illness possibly playing roles, she said. The family disagrees.
“Even if police say this case is closed, we’re not going to stop getting justice,” Ms. Gilbert said. “We’re going to be as loud as we can.”