Rex Heuermann, the man who has been charged with the murders of three sex workers on Gilgo Beach, New York, was charged Tuesday with a fourth murder, according to court documents.

The charges against the suspected serial killer, unsealed Tuesday at the Suffolk County Courthouse in Riverhead on Long Island, are in connection with the death of Maureen Brainard-Barnes, 25, whose remains were found near Gilgo Beach.

Heuermann was considered a prime suspect in her death. He has already been charged in the deaths of Melissa Barthelemy, 24; Megan Waterman, 22; and Amber Lynn Costello, 27, all found in high weeds near Gilgo Beach.

The remains of all four women — known as the “Gilgo Four” — were discovered in December 2010 when authorities were searching for Shannan Gilbert, a sex worker who vanished on May 1, 2010.

Gilbert, 23, was reportedly last seen running through the gated community of Oak Beach after leaving a client’s home, according to a police case timeline. Her remains were not found until December 2011.

Heuermann was connected to the deaths of Barthelemy, Waterman and Costello through cellphone data and DNA obtained from a discarded slice of pizza, authorities said. His wife’s hair was also found at the crime scenes, leading authorities to believe that the items used, such as burlap sacks and tape, came from their home.

He was arrested in July as detectives surrounded him outside his Manhattan architecture office. Heuermann pleaded not guilty to three charges of first-degree murder and three charges of second-degree murder in the killings of Barthelemy, Waterman and Costello.

He was ordered to be held without bail.

The remains of Brainard-Barnes were discovered along Ocean Parkway on Dec. 13, 2010, according to authorities. Her remains were found along with the remains of Costello and Waterman. Barthelemy’s remains were found on Dec. 11, 2010.

All four women worked as Craigslist escorts and were last seen between July 2007 and September 2010, according to the case timeline.

As the search for Gilbert continued, several other sets of human remains were uncovered including the partial remains of Jessica Taylor, the remains of 24-year-old Valerie Mack, a female toddler, a man, the toddler’s mother, and an unidentified person.

Heuermann is not suspected in all of the deaths and he has not been charged in the deaths of Gilbert, Taylor or Mack.