Who is Rex Heuermann, the 59-year-old architect arrested in connection to the Gilgo Beach killings?

• Authorities arrested 59-year-old architect Rex Heuermann in connection to the Gilgo Beach killings.
• Heuermann was investigated in 2007 over whether he falsely identified a building as vacant.
• He was charged with first-degree murder in connection to three of the Gilgo Beach victims.

A string of killings in the Long Island area had stumped authorities for more than a decade until, on Thursday, they arrested a 59-year-old architect and charged him with murder.

The suspect, Rex Heuermann, was taken into custody on Thursday, and his home in Massapequa Park was blocked off on Friday amid a massive media presence in the area. He was charged with three counts of first-degree murder and three counts of second-degree murder on Friday afternoon. Heuermann pleaded not guilty to the charges.

Heuermann owns an architecture firm, RH Consultants & Associates, that was incorporated in 1994. The company's website says that it's been in business for more than 30 years and lists the New York City Landmark Preservation Commission, Catholic Charities, NYC-DEP Sewerage Treatment, American Airlines, and "other major tenants at the JFK International Airport" as clients.

Heuermann's name has come up in connection to his architecture business in the past; the New York City Department of Buildings opened an investigation into Heuermann in 2007 after a crumbling building in Manhattan's central Harlem neighborhood left at least 26 families homeless.

According to The New York Daily News, the DOB was specifically investigating whether Heuermann, who was tapped to renovate the building, falsely identified it as vacant. It was one of multiple jobs tied to Heuermann that the department investigated in 2007; the audits were closed out after the DOB did not find a pattern of false filings or significant disregard for its regulations.

A Twitter user claimed that Heuermann visited another New York residential building as recently as last month and made a bid to replace the building's boiler:

Heuermann's arrest capped nearly 13 years of investigating the Gilgo Beach killings; the first human remains linked to them were discovered in December 2010, and officials have since recovered the remains of 11 victims: nine women, one man, and a toddler. Several of the bodies were found near the Gilgo Beach area.

Authorities said they used DNA evidence to tie Heuermann to three of the victims: Melissa Barthelemy, Megan Waterman, and Amber Costello. They also said he's a prime suspect in the death of a fourth victim.

Heuermann's court-appointed lawyer, Michael Brown, said his client told him that "I did not do this."

"Anybody who's arrested and charged with three murders, well, I should say, obviously, well he's destroyed," Brown said at a news conference on Friday. "He's clearly destroyed about the charges here."

Brown also said that he hasn't yet looked at the evidence in the case but believes it's "extremely circumstantial in nature."

Suffolk County District Attorney Raymond A. Tierney said Friday Heuermann searched how police were using the internet and cell phones to investigate the case. He also browsed for pictures of his victims and their families "compulsively," Tierney said. 

Heuermann grew up in Nassau County and worked in Manhattan, where he was arrested, according to The New York Times. After news of the arrest broke, the actor Billy Baldwin tweeted that he and Heuermann went to high school together.

"Woke up this morning to learn that the Gilgo Beach serial killer suspect was my high school classmate Rex Heuermann," the Baldwin brother wrote. "Berner High School Massapequa, New York Class of 1981," he said, adding, "Married, two kids, architect. 'Average guy...quiet, family man.' Mind-boggling... Massapequa is in shock."

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