The student did not have access to any real weapons.
Deputies state that the individual is in custody and that this originated in SC- the post showed a juvenile male wearing a partial mask holding an apparent assault rifle with the caption "Round 2 of Florida tomorrow".
His parents allowed deputies to search the home.
The sheriff's office said while investigating they discovered a New York Post article detailing that a juvenile in Spartanburg County, South Carolina was arrested for sending the threat.
The Broward Sheriff's Office says the original poster has been arrested by authorities in SC.
Police did not name the Broome High School student. As a result of shooting, 17 people were killed, 20 more were injured.
The minor, whose name can not be revealed due to his age, was charged with disturbing schools, and was transported to the Department of Juvenile Justice facility in Greenville.
School officials say a ninth grader has been arrested after threatening students and staff at Broome High School. We want to thank students that immediately reported the concern tonight which we relayed to our SRO. The student who tipped off local authorities was lauded for their courage.
Superintendent Kenny Blackwood added, "The District would like to commend the student who came forward with information".
Authorities identified the student who posted on Snapchat early Thursday and rushed to his home where they arrested him.
A parent had reported the threat after their child saw the Snapchat photo and alerted them.
The devastation at Marjory Stoneman Douglas High School in Parkland, Fla. was enough to leave schools everywhere on edge but online threats worsened things and even led to a number of false shooting reports Friday.