BREAKING: 13-year-old Tristyn Bailey cause of death revealed, 14-year-old murder suspect appears in court [VIDEO]

A medical examiner in Florida has determined that a 13-year-old girl found dead this weekend was stabbed to death.

As CrimeOnline previously reported, Aiden Fucci, 14, was arrested Monday on suspicion of killing 13-year-old Tristyn Bailey, who was found dead Sunday evening in St. Johns, Florida, hours after family reported her missing.

According to Fox 35, the St. Johns Sheriff’s office said on Tuesday that a medical examiner found that Bailey had died from “sharp force trauma by stabbing.”

A reporter for WOKV said on Twitter that an arrest report shows that Bailey and Fucci were seen walking together at about 1:45 a.m. The boy was seen walking alone nearly two hours later, carrying his white shoes, and told police that he had taken his shoes off because his feet hurt.

The suspect appeared in court on Tuesday to hear the second-degree murder charge against him. He was reportedly ordered held for 21 days in a juvenile detention center. Prosecutors have not yet determined whether he will be tried as a juvenile or an adult.

The St. Johns County sheriff said at a news conference Monday that a resident found Tristyn’s body in a wooded area, but did not reveal the exact location or the condition of the body, except to say that the teen girl was clothed.

READ MORE: SEE IT: Teen suspect in 13-year-old girl’s murder takes selfie in back of squad car, posts with chilling message

A St. Johns County Sheriff’s Office spokesperson confirmed to News4Jax that Fucci is the boy seen in a Snapchat selfie that he captured while in the back of a squad car after his arrest, and posted it with the caption, “Hey guys has anybody seen Tristyn lately.”

The report also confirms that Fucci was not handcuffed at the time. It is unclear why the suspect not been handcuffed or why police did not confiscate his cell phone before putting him in the vehicle.

As previously reported, the St. Johns County Sheriff said at Monday’s news conference that police had been communicating with multiple witnesses, though it is unclear if any were present at the time of the murder.

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