A slew of new evidence was released by prosecutors on Tuesday in the case of alleged Gilgo Beach serial killer Rex Heuermann, including travel records showing Heuermann's family leaving town during the alleged murders, the suspect's illicit online searches and investigators' attempts to secure DNA evidence from his daughter.
The release of evidence comes as Heuermann, 60, was charged with murdering 25-year-old Maureen Brainard-Barnes, who disappeared in 2007 while working as an escort, with prosecutors linking him to her death through DNA and other evidence. Defense attorney Michael Brown entered a not guilty plea on Heuermann's behalf to the second-degree murder charge in Suffolk County Court on Tuesday.
The former New York architect had already been charged in July with murdering three other escorts on Long Island. Like those victims -- Megan Waterman, Amber Costello and Melissa Barthelemy -- the remains of Brainard-Barnes were found in a desolate spot along the ocean near Gilgo Beach in December 2010, prosecutors said.
Prosecutors in a new court filing said Heuermann's now-estranged wife, Asa Ellerup, and his children were out of town when Brainard-Barnes disappeared and was killed, fitting an alleged pattern of Heuermann being home alone when the other three killed.
"As set forth in Exhibit A, travel and cellular telephone billing records had previously established that Defendant Heuermann's wife and children were out of the state during the disappearances and murders of three of the four victims, specifically, Melissa Barthelemy, Megan Waterman, and Amber Costello," prosecutors said, citing documents they obtained during a search of a storage unit leased by Heuermann.
The documents include a credit card statement that shows his wife checked into an Atlantic City hotel July 6, 2007, and stayed through July 20.
"Based on the foregoing, the murders of all four victims occurred at times when Defendant Heuermann's wife and children were traveling out of state, which allowed Defendant Heuermann unfettered time to execute his plans for each victim without any fear that his family would uncover or learn of his involvement in these crimes," prosecutors said.
The new filing also revealed that prosecutors seized two phones from Heuermann at the time of his arrest that they said were held by him "in fictitious names and used for illicit activities." Prosecutors said Heuermann "utilized these phones in furtherance of hundreds of contacts with sex-workers between 2020 and 2023."
Prosecutors additionally revealed Tuesday they seized hundreds of electronic devices from Heuermann's Massapequa Park home and Manhattan office following his arrest.
MORE: Lawmakers look to expand Son of Sam law to cover spouses in wake of Gilgo Beach caseHeuermann used the devices to search for the deceased victims and their family members; the status of the investigation; for software that would assist in wiping or erasing data from computers and other similar digital devices and to purchase digital masking and forensic wiping tools, prosecutors said.
"Defendant's devices also contained the following: A collection of violent, bondage, and torture pornography preceding, during, and subsequent to the disappearances and murders of the aforementioned victims between 2007 and 2010; and prostitution-related searches preceding, during, and subsequent to the disappearances and murders of the aforementioned victims between 2007 and 2010," the filing says.
The new court filing also outlines the lengths prosecutors went to obtain DNA from Heuermann's family, including tracking his adult daughter, Victoria, on a Long Island Railroad train drinking from a gold-colored energy drink can.
Investigators saw her toss the can into the trash. They recovered it and took it for analysis, prosecutors said.
Since Heuermann's arraignment in July, significant DNA evidence was collected in the case, prosecutors said, including from hair found on the buckle of the belt that secured Brainard-Barnes' body. That hair matched the genetic profile of Heuermann's wife. Hairs found at the other crime scenes were also linked to Heuermann’s wife and daughter as well as Heuermann. His wife and daughter are not considered suspects in the case.
The latest indictment marks a significant change in the investigation, authorities said at a press conference after Tuesday's hearing. The "Gilgo 4 investigation" is over, authorities announced, saying the work of the grand jury continues going forward.
Brainard-Barnes' daughter Nicolette, who was only 7 when her mother was killed, spoke to reporters after the hearing.
"While the loss of my mom has been extremely painful for me, the indictment by the grand jury has brought hope for justice for my mom and my family," she said.
Heuermann was once again remanded to Suffolk County jail and the judge set the next court date for Feb. 6.
He previously pleaded not guilty to killing Waterman, Barthelemy and Costello, all of whom were found dead in December 2010.
The deaths of six other victims found near Gilgo Beach between 1996 and 2011 remain unsolved.
-ABC News' Stephanie Ramos, Jack Feely, Gregory Croft and Juwon Funes contributed to this report.