Did someone try to drug or poison a school teacher in Missouri?

FOX's Dave Anthony reports:

Police want to know what happened to a teacher at Smithville High School:

(Roberts) "I do remember him talking about him having a sudden heart problem last week and him going in to see a doctor."

Austin Roberts says his teacher started feeling those symptoms during a class last Tuesday. The school superintendent says they are taking this very seriously as investigators wonder if someone drugged his coffee.

Smithville student Brandon Butts is stunned:

(Butts) "He's an insanely nice guy, I could never see anyone holding anything against him."

What's left of the coffee was sent to a Missouri state lab for testing:

(Butts) "I think that whoever did it should pay the consequences."

Dave Anthony, FOX News.