School officials made a decision to close Wolf Middle School after a threat was made on Instagram that people at the school would die.
Police say it was a precaution.
"Anyone who specifically says a child or children or group will be hurt or killed, there is no question that the threat is imminent to us," said Chief Paul Myszenski.
Myszenski says this investigation started out facing an obstacle. Investigators submitted a search warrant to Instagram, the social media site used to post the threat.
Police say the warrant was not immediately responded to.
Myszenski says the information needed from Instagram was not received until around 3 pm on Tuesday well over 24 hours after the search warrant was submitted
"We submitted them Monday morning and apparently their definition of threat is different than ours," he said.
Officials say until they get the answers they need it's in the best interest of students and staff to stay away from building.
"There is a lot at stake here not only for me, but for superintendent," Myszenski said. "She can't take the chance of any child getting hurt. The school has to be closed down."
Frustrated parent Harry Consiglio spoke about the shutdown of his daughter's school.
"We're really worried," he said. "We don't know what's going on, they're just saying school is down because of a threat."
The school had been closed since Monday but based on new information received Tuesday afternoon, school officials say they are confident no threat exist any longer.
School will be back in session on Wednesday.
But the question still remains if the days the students were forced to stay away, will have to be made up.
"Unfortunately that means for our students that they may have to go into summer," said Andrew McKinnon, assistant superintendent of Center Line Schools.