Teenager arrested and acquitted in connection with his father's death in 2023 is now accused of stabbing his mother to death

A teenager who was arrested and released last year in connection with the fatal shooting of his father in Oklahoma now faces charges in the killing of his mother in Florida, authorities said Wednesday.

The 17-year-old was arrested on suspicion of stabbing his mother to death at his grandmother's home in Auburndale, northeast of Tampa, on Sunday, Polk County Sheriff Grady Judd told reporters.

The teenager is charged with first-degree murder, kidnapping and violating a restraining order, the sheriff's office said. NBC News does not typically name minors accused of crimes.

Judd said he wants to try the teen as an adult. It is not clear if he has an attorney to speak on his behalf.

Two days before the alleged stabbing, the teenager and his mother got into an argument about chores, after which he fled their home in nearby Charlotte County and went to stay with his grandmother, Judd said.

On Sunday, his mother went to Auburndale. The teen called 911 around 6 p.m. and said his mother had fallen on a knife after a long struggle and was bleeding from the neck, Judd said.

When officers arrived, Judd said, the teenager appeared “calm, composed and collected” and asked to speak to a lawyer.

The local medical examiner said the teenager's testimony was “neither plausible nor credible,” Judd said, adding that the blade of the 12-inch kitchen knife used in the alleged stabbing went into the mother's neck.

About an hour and a half before the teen called 911, neighbors reported seeing the woman and her son arguing outside the grandmother's house, Judd said. They saw the teen grab his mother by the hair and drag her into the house, he said.

The grandmother was not at home at the time, he said.

Authorities also learned that the teen claimed self-defense after fatally shooting his father on Valentine's Day last year in Lincoln County, Oklahoma, Judd said. There were no witnesses to the shooting, and the teen said he opened fire after his father pulled a knife on him, Judd said.

The man was shot once in the head and once in the chest, Judd said.

State and local authorities investigated the killing and arrested the teenager on suspicion of premeditated murder, but local prosecutors dropped the charges a month later because they could not disprove the teen's claim, Judd said.

The prosecutor's office that handled the shooting was not immediately available for comment. An assistant prosecutor at the prosecutor's office told NBC affiliate WFLA in Tampa that self-defense could not be ruled out and that is why no charges were filed.

After the shooting, the teenager moved in with his mother in Florida. In November, he was charged with assaulting her and arrested, Judd said. At the time, she disciplined him and revoked his video game privileges, Judd said.

“He pushed her to the ground and trampled on her,” he said, adding that the teenager's grandmother witnessed the attack.

The teenager claimed he was acting in self-defense, Judd said, but the grandmother disputed his account and he was arrested on suspicion of domestic violence, the sheriff's office said.

The outcome of the case was not immediately clear. The sheriff's office in Charlotte County, where the alleged assault occurred, did not immediately respond to a request for comment.