Editor's note: This story contains some graphic details.
The accused Long Island Serial Killer left love notes in his high school crush’s locker, but she and her classmates said they were "shocked" after learning about Rex Heuermann's arrest.
Heuermann, a 59-year-old married father of two and an architect working in Manhattan pleaded not guilty to murder charges connected to an infamous cold case dubbed "Gilgo Beach 4."
Maureen Boyle Holpit, who graduated from high school with Heuermann in 1981, told Fox News Digital that he left "little notes" like, "I think you're pretty" or "I like you. Could like me back?"
The flirtatious notes were anonymous, but Holpit caught him one day, but she never saw him as a threat.
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"He was quiet, kind of shy. He seemed nice, and pleasant. Mild-mannered," Holpit said. "That's all I could really remember of him. I was always nice and kind to him. He seemed to have gotten teased a little bit because he was shy and maybe a little nerdy.
"But there were no indicators or red flags to me now that I'm looking back that he could do something like this."
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Heuermann, a hulking man in stature, allegedly killed three of the so-called "GIlgo Beach 4" and was charged with six counts of murder - a first-degree and second-degree murder charge for each victim.
The counts are connected to the deaths of Melissa Barthelemy, Megan Waterman and Amber Costello, whose bodies were found on Gilgo Beach on Long Island in December 2010.
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Suffolk County District Attorney Raymond Tierney said on Friday that more charges could be filed as investigators continue to work and potentially connect Heuermann to the first "Gilgo Four" victim, Maureen Brainard-Barnes, who was 25 when she disappeared in 2007.
"I didn't see (Heuermann's arrest) at first. My friend called me, and she asked if I saw the news this morning," Holpit said. "I said, ‘No,' and she was telling me the name Rex. That's when I remembered the little love notes, and I was fr****n shocked. I couldn't believe it.
"And just from what I see from other people's comments (on social media), and from the friends that I'm still in contact with, we're just totally blown away and shocked. You just never expect this."
Even actor Billy Baldwin chimed in on his high school classmate Heuermann's arrest.
"Woke up this morning to learn that the Gilgo Beach serial killer suspect was my high school classmate Rex Heuermann," Baldwin tweeted Friday morning.
"Berner High School Massapequa, New York Class of 1981 Married, two kids, architect. 'Average guy… quiet, family man. Mind-boggling… Massapequa is in shock. 23andMe strikes again???"
Officials detailed "thousands" of Google searches that Heuermann allegedly made for various graphic pornography and nearby sex workers.
Fox News Digital is not describing many of the Google searches due to their explicit nature.
Between March 2022 and June 2023, he allegedly made 200 Google searches related to the disappearances and murders of Maureen Brainard-Barnes, Barthelemy, Waterman and Costello, the bail application says.
The Google searches include "Why could law enforcement not trace the calls made by the long island serial killer," "Why hasn’t the long island serial killer been caught," "In Long Island serial killer investigation, new phone technology may be key to break in case" and more.
His lawyer, Michael Brown, said the evidence against his client is "extremely circumstantial" and told reporters that Heuermann repeatedly said, "I didn't do this," through tears.
Brown was given the case Friday, so he's reviewing the evidence and couldn't comment on specific allegations.
READ: CASE AGAINST REX HEUERMANN
"We obviously don't have any evidence. This is the beginning of the case," Brown said.
"Everybody is presumed innocent in our country, there's a presumption of innocence, and we're looking forward to fighting this case in a court of law, not the court of public opinion."
The Gilgo Beach murders have remained unsolved more than a decade after the search for missing escort Shannan Gilbert, 24, first led police to the bodies of multiple sex workers and other victims east of New York City.
Separate from the "Gilgo 4" include the partial remains of 20-year-old Jessica Taylor, which were found in March 2011 Near Gilgo Beach. Authorities said part of Taylor’s body was discovered eight years earlier and 40 miles away in Manorville, New York.
Days later, three more sets of human remains were discovered alongside Ocean Parkway. The first was 24-year-old Valerie Mack, whose partial remains had also been found in Manorville years earlier.
An unidentified toddler was found near Mack, according to the official website dedicated to the case.
Two miles west, police discovered the skeletal remains of an unidentified Asian man — or transgender woman — believed to be 17 to 23 years old.
A week later, in April 2011, two more sets of partial remains were found along Ocean Parkway. The first were those of the woman known as "Peaches," believed to be the mother of the toddler found the week before.
Part of her body had been previously discovered in Hempstead Lake State Park in 1997. The second was the skull of a woman who was linked to remains found on Fire Island in 1996.
Fox News' Michael Ruiz and Adam Sabes contributed to this report.
