16-Year-Old Girl Charged With Making Threats Against Miami Northwestern Senior High

MIAMI (CBSMiami) -- A 16-year-old girl will remain in the Miami-Dade Juvenile Assessment Center until a hearing next week following her arrest for making a threat against a school on social media.

The teen, who CBS4 News is not identifying because she is a juvenile, is charged with a felony count of written threats to kill or do bodily injury.

According to the police report, students from Miami Northwestern Senior High were receiving threats via Instagram.

The report states the messages were being sent from the Instagram username @MiamiSchoolKiller.  In the message, the person wrote, "Don't go to school tomorrow, I will blow up Miami Northwestern Senior High School and you will be the first to die."

The teen was identified via investigative tools and located at her home on Monday. Investigators say she is a student at the school.

She was the second South Florida student to be arrested on  Monday for making school threats.

A 15-year-old boy was also charged for posting a threat involving Miami Senior High School that was then altered by other people and reposted on social media, affecting about a dozen other schools.

All of those threats were deemed to be non-credible.

"There are copycat threats against schools which quite frankly is unacceptable," said Miami-Dade School Superintendent Alberto Carvalho.

The 15-year-old is also being charged with a felony count of written threats to kill or do bodily harm.

"We take these matters very seriously. We investigate every one of these threats and we're very successful in identifying the perpetrators," said Carvalho.

The 15-year-old appeared in court Monday morning. His attorney said there wasn't any actual proof that the teen was the one to make the threat.

Carvalho said the student was tracked down with the help of the FBI and Secret Service who worked together to identify the IP address that the threat came from.

Last week, the Broward Sheriff's Office arrested a 17-year-old for a threatening message posted on social media regarding Marjory Stoneman Douglas High School in Parkland, site of the Valentine's Day massacre that killed 17 people and left 17 others injured.

The 17-year-old Stoneman Douglas student's arrest affidavit says he wrote that he felt like a school shooting the next day, and he hoped the other students wouldn't snitch on him. The teen's mother says he meant it as a joke.

The threats come shortly after a 15-year-old sophomore opened fire at his Michigan high school, killing four students and injuring others.