Tristyn Bailey,the 13-year-old Florida girl who was stabbed to death earlier this month, was allegedly stabbed 114 times before her death while fighting off her killer, authorities said Thursday.

The 14-year-old boy accused of killing Bailey has had his charge upped from second-degree murder to first-degree, and will be charged as an adult, 7th Judicial Circuit State Attorney R.J. Larizza said during a news conference Thursday.

PEOPLE has not yet named the suspect because he is a minor.

“It brings me no pleasure to be charging a 14-year-old as an adult with first-degree murder,” Larizza said,NBC News reported. “But I can tell you also the executive team and I reviewed all the facts, all the circumstances, the applicable law and it was not a difficult decision to make, that he should be charged as an adult.”

Tristyn Bailey.Courtesy Tanya White

Tristyn Bailey

Larizza said that of the 114 stab wounds Bailey sustained, at least 49 were to her hands, arms and head,USA Todayreported. “They were defensive in nature,” he said, adding that “premeditation could be inferred certainly from just the sheer number of stab wounds that Tristyn Bailey had to suffer.”

“Every time that arm went back, and every time that arm went down, that was premeditation,” Larizza said.

“To say that it was horrific could arguably be made as anunderstatement,” he said.

Tristyn Bailey.gofundme

Tristyn Bailey

Elsewhere in the press conference, Larizza said that the 14-year-old suspect — who has been held at a juvenile detention center since he was arrested on May 10 — is being transferred to an adult prison, though he will be held separately from the adult inmates.

“It’s a sad decision and a sad state of affairs,” Larizza said.

A motive has not yet been determined.

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The arrest report also alleges that deputies found a security video that showed two teens — now believed to be the suspect and Tristyn — walking east on a suburban street at approximately 1:45 a.m. on the day of her murder. The video later showed just one person — believed to be the suspect — holding a pair of shoes while walking west around 3:27 a.m.

Tristyn Bailey.sjso

Tristyn Bailey

The suspect allegedlytook a selfie in the back of a patrol carthat was shared on Snapchat. He was displaying a peace sign and captioned the photo, “Hey guys has anybody seen Tristyn lately?” The photo was taken on the day of her murder while she was still missing, NBC News reported, as he was taken in for questioning as a witness.

His lawyer has not previously returned PEOPLE’s requests for comment.

Her family issued a statement on Thursday, saying that they “will seek to keep Tristyn’s memory alive and the spirit of the community,“USA Todayreported.

source: people.com