Cousins faces a preliminary charge of murder in Tuesday's shooting death of 21-year-old Andrew Boldt of West Bend, Wis. Both were seniors in Purdue's engineering school.
Cousins has a court appearance scheduled Thursday.
Police haven't disclosed a motive for the shooting. Purdue Police Chief John Cox did not return phone calls Wednesday.
Purdue Professor Thomas Talavage describes Cousins as intense and aggressive about his projects. He says Cousins "didn't like to be told he was wrong."
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