HAUPPAUGE, N.Y. (AP) — Law enforcement authorities in New York have scheduled a news conference Friday to announce a new development in their investigation of multiple sets of human remains found along the Long Island coast, some of which have been blamed on the work of a serial killer.

Rex Heuermann was arrested last month in the deaths of three women and has been named a prime suspect in the killing of a fourth. The remains of those four women were discovered in 2010 along a coastal parkway near Gilgo Beach.

Police, though, have continued to investigate the deaths of six other people whose skeletal remains were found along the same, long stretch of coastline.

Among them was a woman, long nicknamed “Jane Doe No. 7” by investigators, whose partial remains were first discovered in 1996 on Fire Island. More of her bones were later found near Gilgo Beach in 2011.

Police have been trying to figure out her identity for 26 years.

Other unidentified remains belong to a woman nicknamed “Peaches” by investigators after a tattoo on her body. Some of her remains were discovered stuffed inside a plastic tub in Hempstead Lake State Park in 1997, others turned up near Gilgo Beach in 2011, along with the remains of an unidentified toddler believed to be her daughter.

Authorities have said Heuermann, who lived in Massapequa Park across the bay from where some of the bodies were found, is unlikely to be responsible for all the deaths.

Investigators zeroed in on Heuermann as a suspect in the slayings of four women — Melissa Barthelemy, Megan Waterman, Amber Lynn Costello and Maureen Brainard-Barnes when a new task force formed last year ran an old tip about a Chevy Avalanche pickup truck through a vehicle records database.

A hit came back identifying one of those make and models belonging to Heuermann, who lived in a neighborhood police had been focusing on because of cellphone location data and call records, authorities said.

Detectives said they were later able to link Heuermann’s DNA to a hair found on a restraint used in one of the killings.

So far, he has been charged in the deaths of Barthelemy, Waterman and Costello. Prosecutors say they are working to charge him with Brainard-Barnes’ death, but have not yet done so.

Through his lawyer, Heuermann has denied killing anyone and pleaded not guilty.

Investigators spent nearly two weeks combing through Heuermann’s home, including digging up the yard, dismantling a porch and a greenhouse and removing many contents of the house for testing.

Earlier this week, prosecutors said they have begun providing Heuermann’s lawyer, Michael Brown, with reams of evidence including autopsy findings, DNA reports and crime scene photos.