South Portland High School was locked down for about an hour Friday morning before all students were sent home at 11:45 a.m.

All of the school’s students and staff are safe, according to district officials.

At 9:30 a.m. high school officials saw a “suspicious individual” on school property, according to a joint news release sent out by the South Portland police department and school district.

The school’s resource officer believed the individual had a weapon and attempted to detain him, the release says. The individual, who the release refers to as a juvenile, began to flee. The officer caught him and took him into custody, according to the release.

The school initiated a lockdown “out of an abundance of caution,” the release says. “The incident is still under investigation to determine if there will be criminal charges.”

Police found the juvenile was carrying an airsoft gun replica rather than a firearm, according to a second message to the community from Superintendent Tim Matheney.

Matheney said that former student Tristan Hamilton, 17, who was arrested in April and charged with trying to recruit another person into a scheme to kill members of the school community, was not involved in the incident Friday.

The juvenile apparently did not intend to harm anyone Friday, Matheney said.

“We realize that today’s events were quite unsettling for all involved. We encourage families to reach out to your student’s counselor or a member of the SPHS administrative team if there’s anything we can do to support your student when school resumes on Monday.”

Neither the district nor the police department responded to voicemails left by the Press Herald.