Authorities believe a woman found slain in her Terrytown apartment Monday was sexually assaulted, choked and stabbed to death by a neighbor who was living in the United States illegally and who had faced a rape allegation two years ago, Jefferson Parish Sheriff Newell Normand said Wednesday.

Irwin Gomez Colon, 31, was booked Tuesday on a count of second-degree murder in the grisly death of Nancy Yahaira Gonzalez, 33, who was most likely killed Saturday night and whose corpse was left with her 4-year-old son for more than 30 hours before authorities discovered her.

Gonzalez's son, Jeremy, remained in state custody Wednesday, said his father, Jhoel Ferreras, Gonzalez's ex-husband.

Ferreras said he was preparing to go to court Thursday to try to get custody of his son while coming to terms with what happened to Gonzalez, who also was in the U.S. illegally but whose husband and son are both U.S. citizens, according to Normand.

"It was an act of cowardice," Ferreras said of the allegations against Gomez. "To leave a child abandoned after (doing) something like that — there is no name for that."

Wednesday marked the first time that authorities described how Gonzalez was killed.

A native of the Dominican Republic, she had separated from her husband and moved to an apartment in the 2100 block of Empire Place in February in search of work.

She had made it a habit to visit with a neighbor, Aneli Vargas, while drinking coffee each morning. However, she did not show up either Sunday or Monday to do that, and she had not been heard from since sending a text message to a friend about 7:30 p.m. Saturday.

Vargas said she and other friends of Gonzalez became worried and eventually knocked on her door. When there was no answer, one friend went to a window on the side of the ground-floor apartment. Jeremy, the son, soon opened the blinds, and the friend spotted Gonzalez's body on the floor, prompting the group to call the Sheriff's Office.

Normand said Gonzalez had been stabbed more than 20 times, most of them to her back. There also were signs that, while fighting for her life, she had been choked and that sex had been forced on her, Normand said.

Jeremy was physically unharmed and was put in the care of state officials, Normand said.

Suspicion soon zeroed in on Gomez, whose front door was just across the parking lot of the apartment complex.

A complex resident identifying himself as Carlos Hernandez said he saw Gomez emerge from Gonzalez's apartment about 10:30 p.m. Saturday. Gomez appeared to be bleeding from his right arm, holding a folded white towel as he walked toward some nearby trash bins, Hernandez said.

Gomez later walked back to Gonzalez's apartment and remained there for a bit before returning to his own place, Hernandez said.

Gomez behaved normally Sunday and Monday, even after Sheriff's Office deputies descended on Gonzalez's apartment, Hernandez said. "He was acting like he didn't have a care in the world," he said. 

Normand said deputies obtained a warrant to search Gomez's apartment. Gomez told them he was acquainted with Gonzalez but hadn't seen her for weeks. Yet deputies were skeptical, given that he had cuts to his right palm and upper right arm, Normand said.

Gomez said he got his wounds working on a construction site, but neither his fellow laborers nor his supervisors backed up his story, according to Normand.

He was booked on second-degree murder, a crime that in Louisiana calls for mandatory life imprisonment.

Normand would not say whether deputies had recovered the weapon used to kill Gonzalez, but he said a search of Gomez's apartment had yielded "items of potential evidentiary value" that were still being processed.

This is not the first time authorities have leveled a serious charge against Gomez, a Honduran national.

New Orleans police jailed him on counts of first-degree rape, second-degree kidnapping and domestic abuse battery involving strangulation about two years ago, but prosecutors later dropped the charges.

He had been arrested on a drunk-driving accusation that same year as well. In 2013, Normand said, Gomez was documented as an illegal immigrant in Texas, having entered the country through Mexico.

Hernandez on Thursday said he was struggling to grasp Gonzalez's violent end, but he seemed content that justice might be done.

"There's always an eye out there watching everything you do," he said. "Always."

Miscellaneous notes 

-- Ferreras said it was his birthday, April 14, when he last saw Gonzalez. During that visit, Ferreras gave their son a bicycle as a belated birthday present. Gonzalez threw a party to celebrate the boy's birthday on April 8, but Ferreras couldn't attend it due to work. 

-- Ferreras said he is from the Dominican Republic. Normand said Jeremy was born in Puerto Rico, a U.S. territory. 

Follow Ramon Antonio Vargas on Twitter, @RVargasAdvocate.

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