Authorities on Long Island are vowing to continue investigating a string of killings known as the Gilgo Beach murders after charging an architect in the deaths of three of the 11 victims.

Rex Heuermann, 59, is accused of killing Melissa Barthelemy, Megan Waterman and Amber Costello over a decade ago. He is also considered the prime suspect in the death of another woman, Maureen Brainard-Barnes.

Their bodies were bound and hidden in thick underbrush along a remote beach highway across the bay from the Massapequa Park community where Heuermann has lived all his life. Investigators have said it’s unlikely just one person killed all the victims.

“We’re going to continue to work, investigate, and try to get a small measure of closure for all the victims’ families,” Suffolk County District Attorney Ray Tierney said.

Heuermann, 59, was arrested late Thursday, a year and a half after authorities formed an interagency task force with investigators from the FBI, as well as state and local police departments, aimed at solving the case. He was charged Friday.

Heuermann was first identified as a suspect in March 2022, when detectives linked him to a pickup truck that a witness reported seeing when one of the victims disappeared in 2010. In March, detectives recovered Heuermann’s DNA from a pizza crust he discarded and matched it to evidence found on one of the victims, authorities said.

“They never stopped working and will continue to work tirelessly until we bring justice to all the families involved,” Suffolk County police Commissioner Rodney Harrison said.

Heuermann was ordered jailed without bail after his lawyer entered a not guilty plea on his behalf at an arraignment Friday in state court in Riverhead. In denying bail, Judge Richard Ambro cited “the extreme depravity” of Heuermann’s alleged conduct.