Workers spraying pesticides on a sugar cane field discovered the badly decomposed body in a ditch just south of Baton Rouge.
Lyntell Washington, a middle school administrator, had been missing since last week. Police began looking for the 40-year-old after finding her 3-year-old daughter wandering alone in a Baton Rouge parking lot near her mother's abandoned vehicle.
The body turned out to be Washington's. She died from a gunshot wound to the head, and she was seven months pregnant.
On Friday, police arrested Brookstown Magnet Honors Academy assistant principal Robert Marks in his co-worker's slaying, alleging that the pair may have had an affair that Washington threatened to expose, the Associated Press reported.
Authorities say they are still determining a motive, as Marks has told detectives very little, Baton Rouge police spokesman L'Jean McKneely told the Advocate.
"We continue to press him for information and still no answer and still no emotion," McKneely told the Advocate. "This is a heinous and senseless crime."
But police pointed to a text message, noted in an affidavit, as showing Marks knew about the pregnancy, the Advocate reported.
In one message, Washington asked Marks whether he was "attempting to avoid his responsibilities with 'our unborn daughter,'" the report read, according to AP.
Marks's attorney, Lionel Lon Burns, said his client denies any involvement with the death of Washington. The attorney described the two as "friends" but said he wouldn't comment on the allegation that Marks was the father of the woman's unborn child.
"I'll let the Baton Rouge Police Department provide the sensationalism," AP reported Burns as saying. "I'll let the facts come out in court."
Burns added: "His wife stands firmly by his side."
At the time of Friday's arrest, Marks was already in custody on charges related to Washington's 3-year-old, including aggravated kidnapping and desertion of the child. He now also faces first-degree murder and first-degree feticide charges.
Burns said police tried to get statement from Marks despite his requesting a lawyer and asserting his right to remain silent, the Advocate reported. A police report includes an alleged admission from Marks of an affair.
The defense attorney also said it was "reckless" for the police department to release statements from Washington's 3-year-old child. She reportedly told investigators her mother was "sleeping" and "in the lake," and that "Mr. Robbie" had hurt Washington, the Advocate reported, citing a police report.
An autopsy showed Washington died from a gunshot wound to the head and there was no trauma to the fetus, WAFB reported.
Blood was found in Washington's abandoned car. McKneely told the Advocate police are still investigating where the shooting took place, and no gun has been found.
Washington's death has shaken the East Baton Rouge Parish schools community. Superintendent Warren Drake said they were "deeply saddened" by the "tragic loss" of Washington and her unborn baby. (Parish is the equivalent term to county in Louisiana.)
"Ms. Washington was a treasured member of our team, and will be remembered for the impact she had on the many lives she touched through her work in our district," Drake said in a statement. "We will continue to offer support to Ms. Washington's co-workers and students during this difficult time."
Lana Williams taught with Washington at her previous school. She told the Advocate Washington "was one of the most generous people I knew."
"When she was actually teaching, even when she was low on money, she was doing everything she could for her students, buying materials and bringing them in," Williams said.
LaTafta Spivey told the newspaper she last spoke with Washington in March. "You're going to be an aunt!" Washington told Spivey at the time, the Advocate reported.
But the friend wasn't happy when she was told about the father, described only as "Robert," and told Washington "I don't get a good feeling from this."
Since Washington went missing, Spivey has been unable to sleep.
"I can't express to you how beautiful her spirit was," Spivey told the newspaper. "I'm very sad."
Elahe Izadi is a general assignment national reporter for The Washington Post.
(c) 2016, The Washington Post · Elahe Izadi · NATIONAL, COURTSLAW · Jun 18, 2016 - 12:40 PM