Barrie Police stopped by St. Joseph’s Catholic High School in north Barrie due to a security concern. In a post on social media, police say officers will be on school grounds on Wednesday, as a cautionary step, after online threats were made against a group of students at the school. Police did not share any details of the nature of threat or the group the threat was directed toward. “We treat all threats, whether online or otherwise, very seriously,” Barrie Police said in a statement to CTV News. “Our officers will remain at the school throughout the day as a precautionary measure. The safety of students and staff is our main priority,” police added. The Simcoe Muskoka Catholic District School Board tells CTV News the threat posted online was targeting a small group of students, but classes resumed as normal. “We always take these matters seriously and follow very specific protocols to respond,” the school board said in a statement to CTV News. The board added it was working with Barrie Police to ensure the safety of the students. A letter regarding the incident was sent to parents on Monday night, the school board says. The letter reads in part “at this time we do not know who was responsible for writing the threats and we are asking for anyone who has information to contact the office.” The letter went on to thank students who notified school staff about the threats made online. “We encourage families to have conversations with their children about the seriousness of making threats - even if they are outside of school hours or online,” the school board said in the letter.