The man accused of killing a Concordia University student appeared to finally show some emotion during day four of his preliminary hearing in Montreal.

Until yesterday, Luka Magnotta had remained mostly impassive during the first days of proceedings, as he sat shackled in his fortified prisoner's box.

But on Thursday, the 30-year old seemed to wipe away tears as a Montreal police investigator gave evidence. 

Magnotta is charged with first-degree murder in the slaying last May of 33-year old Jun Lin, a Concordia University engineering student.

Lin's father, Diran Lin, was also back in court yesterday after leaving the courtroom in tears earlier this week.

The hearing will determine whether there is enough evidence to send Magnotta to trial.

The evidence being heard is subject to a publication ban.