Newly resurfaced body-cam footage from the Taylor Parker case shows the convicted killer inside an Oklahoma hospital desperately trying to convince officers she had just delivered a baby … when in fact it was the fetus she had cut out of her murdered friend.

In the footage, obtained by TMZ from the Bowie County Court, investigators are seen at her bedside, explaining the situation at hand — telling Parker they already are certain she’s killed Reagan Simmons-Hancock and stolen the baby out of her uterus … they’re just trying to figure out why, mentioning depression and medication.

Parker appears visibly distressed as she repeatedly insists to law enforcement and hospital staff that she had just gone into labor while driving — however cops are not buying her narrative, telling her “we know you did it.”

Taylor eventually caves in and begins to cry, expressing she’s upset that her friend is now dead and that her “head’s been hurting” … adding she had a stroke in 2015.

According to prosecutors, Parker had been posing as pregnant for months before killing Simmons-Hancock — who was more than eight months pregnant, and removing the unborn child via a makeshift C-section.

The baby later died and Parker was ultimately convicted of capital murder and sentenced to death … Taylor is still awaiting her execution date and is currently the youngest woman on death row in Texas.