Washington College in Chestertown, Md., announced it is closing its campus and suspending classes for the day following a suspected gun threat on school grounds early Monday.

Tweets and a message on the school's website advised students on campus to shelter in place, and warned faculty and staff not to report to work, reported the Associated Press. Tweets also advised everyone not to take unnecessary action until they heard from officials.

College spokesperson Michael O'Connor said college officials were notified early Monday by parents of sophomore Jacob Marberger that he had returned to his home outside Philadelphia and retrieved a firearm, but have since been unable to reach him.

His current location and where he is headed is unknown, but it is believed he is still in Pennsylvania, reported Reuters. Chestertown police are currently treating the student as a missing person, who was last seen driving a green Range Rover.

"Due to an abundance of caution the college has decided to close campus for the time being and asks all students and staff on campus to shelter in place," the statement said. "Anyone off campus should stay away from campus until further notice."

Campus public safety and local law enforcement officials are conducting a sweep of the parking lots and campus buildings as they search for the missing student. Furthermore, students in three residence halls have been moved to facilitate the search of those buildings, according to FOX News.

The private school on a 112-acre campus was founded in 1782. It has about 1,450 students.