A Florida woman has been accused of murdering her boyfriend’s 9-year-old daughter — after her home security cameras caught her beating the girl and getting her 103-pound Rottweiler to maul her, according to authorities.

Tyshael Elise Martin, 34, claimed to have discovered little Jamaria Sessions unresponsive when she went to wake her up for a family vacation to California on June 17, WESH 2 reported.

But investigators sought out footage from their Montverde home’s security system because the little girl was covered in cuts, bruises, burns and even bite marks, the outlet said.

The footage showed Martin egging on a 103-pound pet Rottweiler that then “viciously attacked” the helpless youngster, WESH 2 said, citing the probable cause affidavit.

Martin was also seen kicking the girl until she was motionless, as well as dragging her across the floor and hitting her, the affidavit said.

“I’m fixin’ to kill her,” she appeared to say during the vicious attack, officials said.

Jamaria’s death was ruled a homicide after the medical examiner listed blunt force trauma to the head and thermal injury to the foot as the cause of her death.

The youngster — the daughter of Martin’s boyfriend, Lojuan Sessions — was frequently subjected to punishments such as prolonged wall sits, being struck with objects, and other forms of abuse, investigators later learned, according to the reports.

The Lake County Sheriff’s Office called it “the worst case of aggravated child abuse we’ve ever seen,” according to Fox 35.

Jamaria’s grandmother, Althea Chenault, told the outlet: “That’s a baby, a beautiful little girl now gone.”

Martin was arrested on felony charges of first-degree murder, aggravated child abuse, and child neglect, according to the sheriff’s office. She remains in jail without bond, court records show.