Troubling journal entries have been revealed of a Maryland student who is charged with bringing a loaded gun to his Clarksburg High School classroom and telling detectives he did so to protect against a possible mass shooter.

That’s according to new court documents filed in the case of Alwin Chen, the honor student who was arrested just one day after the massacre at Marjory Stoneman Douglas High School in Parkland, Florida that left 17 people dead.

In one journal entry that was dated May 1, 2017, Chen allegedly wrote, “I might start doing some vigilante operations. I don’t plan on killing people, but I’m surely going to hit evil people.”

In another entry, which Montgomery County prosecutors revealed in court documents obtained by WJLA, he wrote, “Sometimes I think I am crazy or mentally ill, but I hide it and refuse to admit it because I know how to cope and blend into society, but it’s just too lonely.”