WEST CALDWELL, N.J. (CBSNewYork) – A man was behind bars Sunday after allegedly posting a threat to social media which triggered a security scare at a New Jersey high school.

Police say Michael Schmitt, 18, of West Caldwell, sent the threatening message to students of James Caldwell High School.

Students at the school were on stage for a music event when they were ordered to shelter in place around 2:30 p.m. Saturday. The school was locked down and later evacuated.

As CBS2’s Lisa Rozner reported, it was supposed to be day-long Music Marathon. Instead, students, parents and teachers found themselves fearing the worst, just 10 days after the deadly school shooting in Parkland, Florida.

“I was about to play for my jazz band,” said Ryan Stevens. “But then one of my friends saw someone with a police officer who was heavily armed.”

The crowd split up and hid in classrooms.

After 30 minutes, police said there was no danger.

Detectives from the West Caldwell Police Department located Schmitt and took him into custody without incident.

Students told CBS2 the post was a song about shooting someone in the head and included JCHS in the title.

No one was hurt in the incident. The principal told students counselors will be on hand Monday if they need to speak with someone regarding the incident.

Anyone with information is asked to call West Caldwell Police at 973 226 4114.

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