A Canadian who allegedly killed and dismembered a Chinese student pleaded not guilty in a court trial here on Monday as his lawyer said he suffers from schizophrenia - a mental illness that can exempt him from criminal responsibility.

Luka Rocco Magnotta, 32, is charged with the first-degree murder of Jun Lin, 33, a computer engineering student at Concordia University, in 2012 in Montreal, committing indignities to Lin's body and broadcasting obscene materials.

Magnotta is accused of dismembering Lin and mailing body parts to Canadian political parties and to two elementary schools, which horrified Canadians and garnered headlines around the world.