ST. LOUIS (AP) — A St. Louis college student who was charged Wednesday with shooting an administrator in a dispute over financial aid has a history of mental illness and may not have been arrested after his probation for a 2009 knife attack was revoked in May.

Prosecutors charged 34-year-old Sean Johnson with first-degree assault, armed criminal action and two firearms violations in Tuesday’s attack at the Stevens Institute of Business & Art. He doesn’t have an attorney yet and a woman who answered the phone at his home declined an interview request.