CHARLOTTE, N.C. — There were more than just school buses at morning drop off at Coulwood Middle School, police cars and concerned parents on campus after a 13-year-old student was arrested, admitting to posting a threat on Instagram. 

A parent posted an image on Facebook Wednesday night, saying her son got a message on social media warning students not to go to Coulwood Middle School Thursday. 

It included a photo of a gun. 

They can't even be safe at school. I think it's inappropriate for anyone to joke about a threat period. With everything going on and how many shootings already happening, for me it’s just scary," said Portia Hudson who has a son at the school.

Charlotte-Mecklenburg Police confirmed early Thursday morning that the 13-year-old student who created the post said it was just a joke. 

“My girls, they're not allowed on there, they're too young. It’s not healthy for them,” said Ana Morales.

According to police, officers searched the home of the teen and no firearms were located. 

"It appears that the student simply obtained a photograph of a firearm online but does not actually possess a gun," CMPD said.   

This is a developing story. Stay with NBC Charlotte for the latest as more information becomes available. 

CMPD investigating social media school threat