DENVER -- The lockout at South High School was lifted on Friday afternoon at approximately 12:40 p.m.
Police have located the juvenile accused of making a threat.
This is the third day in a row a lockout has been issued for South High School.
Denver Public Schools' Department of Safety and the Denver Police Department provided an update about 4 p.m. Friday.
DPD said the juvenile involved is a male. He was arrested at his home on an unrelated probation violation. Police do not believe he had immediate access to guns.
“The young man ran away from home. The parents had no knowledge of his whereabouts, so they then reported that to the school," DPD said.
DPS said it believes the threat was very specific.
“We knew who we were looking for and that we could protect the community and our students," DPS said.
One parent said she kept her daughter home from school during the lockouts because she feared for her safety.
“We have to protect our family," Tracy Burks said. “I’m considering the alternatives of how I can educate my children because I don’t feel safe for them anymore."
The suspect's parents have been cooperative, according to police.
In a letter to families, principal Bobby Thomas wrote that a student, who is a minor, allegedly made a threat against the school.
Officers had a heightened concern for the school and the individual student.
Police sent out a statewide alert for the student so he could be arrested based on an outstanding warrant, Thomas said.
During the lockout, students had to remain inside the building and parents or guardians could not sign anyone out.
Advanced Placement exams scheduled for Friday were postponed.