CHICAGO (CBS) — Two high schools in the northwest suburbs will be holding classes online on Thursday, as police investigate threats of a shooting found on social media.

Leyden High School District 212 Superintendent Dr. Nick Polyak said East Leyden High School in Franklin Park and West Leyden High School in Northlake will have an “e-learning day” on Thursday due to the threats.

During e-leanring days, students and staff stay home, and classes are held online.

Polyak said school officials decided to keep students and staff at home on Thursday due to “a large volume” of posts on social media threatening a shooting.

“We take the safety of our students and school community very seriously. We would like to create some time and space for our local law enforcement professionals to look into these issues,” Polyak said in a letter to parents.

The superintendent said the district would decide later on Thursday whether or not Friday would be an e-learning day as well.

East Leyden High School was placed on lockdown Tuesday morning, and students were later sent home early, after a boy was stabbed in the neck during a fight with a schoolmate in a second-floor hallway.

The victim was taken to the hospital and is expected to make a full recovery. His attacker was arrested.