The Commack Union Free School District was on lockout Tuesday after a staff member reported a suspicious person on school grounds.

According to the school district, a staff member at Sawmill Intermediate School saw someone with what appeared to be a gun tucked into the back of his pants at around noon. The person was seen near a side parking lot where he got into his car and drove off.

Following an investigation, authorities determined the person to be a police officer who was at the school for his child.

By the time the school found out who the person was, the lockout was already in place. Suffolk County police were at the school and school security was also out during dismissal.

School officials alerted parents about the lockout. The school superintendent's message to parents said in part, "Suffolk County police are actively investigating and responding accordingly. I will provide an addition update as soon as I have more information. Most importantly, the children are safe in the buildings."

Many parents still rushed over to the school to pick up their children - fearing the worst.

"It's a rough day - it's sad we're in this current situation going on," says parent Danielle Finocchiaro. "This is unfortunately the norm; we're all trying to get through it."

Schools in the district were dismissed on time but after-school activities were canceled.