Gilgo Beach murders: Who is the suspect, Rex Heuermann?

A Long Island architect has been charged with murder in the deaths of three of the 11 victims in a long-unsolved string of killings known as the Gilgo Beach murders.

Rex Heuermann, 59, has lived for decades across a bay from where the remains were found. He is charged with first and second degree murder in connection with the deaths of three victims – Melissa Barthelemy, Megan Waterman and Amber Costello. 

Authorities said he's also the "prime suspect" in another killing.

Heuermann was taken into custody in Massapequa late Thursday, near where investigators were seen searching his home Friday. He is expected to be arraigned Friday afternoon in state court in Riverhead.

A message seeking comment was left with his lawyer. Voice and email messages were left at Heuermann’s Manhattan office and at possible numbers for his home and family Friday.

Suffolk County prosecutors are asking Heuermann be held without bail, citing the "heinous nature of these serial murders," as well as recent searches he made for sadistic materials, including sexually exploitive images of children and photos of the victims and their relatives.

He is scheduled to be arraigned Friday afternoon in state court in Riverhead. Officials have scheduled a press conference to discuss the charges.

The official was not authorized to publicly discuss details of the investigation and spoke to AP on condition of anonymity.

A message seeking comment was left with his lawyer. Voice and email messages were left at his Manhattan office and at possible numbers for his home and family Friday.

The Associated Press contributed to this report.