Gilgo Beach murders: What we know and what we don’t about the ongoing investigation

The arrest of Rex Heuermann for some of the Gilgo Beach murders represents a major advancement in a case that has baffled law enforcement and frustrated victims’ families for more than a decade.

Prosecutors and law enforcement say the breakthrough was a combination of new forensic techniques, cell phone locations as well as a new approach to pursuing leads in the case.

But there are still many questions: Heuermann was charged with three murders, and is likely to be charged with a fourth. But over the years, at least 11 victims were cited as being part of the Gilgo Beach murders though officials are not yet connecting Heuermann to those killings.

What are the Gilgo Beach murders?

In May 2010, Suffolk County Officer John Malia and his K9 partner Blue were conducting a training exercise along Ocean Parkway at Long Island’s Gilgo Beach when the pair found a set of human remains belonging to Melissa Barthelemy, according to court records. Shortly after, investigators discovered three more bodies — those of Maureen Brainard-Barnes, Megan Waterman and Amber Costello. The women, known as “the Gilgo Four” were described as “petite” sex workers in their 20’s and all had been found in close proximity, bound in tape or belts and wrapped in a burlap material.

By 2011 seven more bodies were found — five women, one man and a toddler — in remote parts of the beach, though the manner of their deaths and the conditions of their remains differed from the Gilgo Four and their killings may have pre-dated the others.

Police were flummoxed for years and drew criticism for not prioritizing the investigations because most of the victims were sex workers.

Who did they arrest this week?

Rex Heuermann, 59, is an architect and consultant living in Massapequa Park, NY on Long Island, just about 15 miles from where the bodies were discovered. He had an office in Manhattan where he was arrested Thursday, officials said. On Friday…