The trial for a 24-year-old man accused of killing five young people at a house party two years ago continued in a Calgary courtroom on Tuesday.

Matthew de Grood is charged with five counts of first-degree murder in the deaths of Joshua Hunter, Lawrence Hong, Zackariah Rathwell, Kaiti Perras and Jordan Segura at a house party in the city’s northwest in April 2014.

Police say the attack was Calgary’s worst mass killing and officers who were called to the scene said three men were already dead inside the home on Butler Crescent when they arrived.

A woman was also found inside the house with serious injuries and a fourth man was discovered outside. Both later died in hospital.

On Monday, de Grood pleaded not guilty to the charges but admitted to killing all five in an agreed statement of facts.

*Warning: This story contains graphic details that some readers may find disturbing.*

In the agreed statement of facts de Grood's family said they began noticing a change in his behavior in the weeks prior to the attack and court heard that he began posting strange comments on social media.

According to the statement, de Grood was not seen using alcohol or drugs at the party and put on a pair of blue latex gloves, after he arrived.

The statement of facts said the stabbings occurred shortly after de Grood had a conversation with Rathwell about Buddhism.

"I asked him to give me my space. We were walking toward the knife block, so I decided to shoot first because I didn't know what he was going to do so I stabbed him," de Grood is quoted as telling police officers.

"Then the people on the couch saw and obviously started freaking out, so I killed them from left to right as quickly as I could. The girl ran into the corner so I went and stabbed her. I said I'm sorry I have to do this. Then the guy from the kitchen wasn't dead. I had to hunt him down. Then I just left."

He is also quoted as saying that "I just want to say that when I stabbed them I tried to do it mercifully. I aimed for their heart. They put up a struggle, which made it hard, but so you know it wasn't sadistic or anything."

A number of witnesses were called on Monday and a K-9 Unit officer told the court that de Grood did not react to pain after a police dog bit him during the arrest.

The assistant manager of the grocery store where de Grood worked also took the stand and said that the accused was “an all-around good person” but “wasn’t himself” the month of the stabbings.

The families of all five victims delivered 'tributes' in front of the court on the second day of the trial.

“It’s a very unusual situation. It’s not a process that’s contemplated by the Criminal Code or by our traditions but this is a unique case and it was agreed between myself and the Crown and Justice Macklin that it was important that the families of the victims had the opportunity to speak and I hope it gives them comfort,” said Allan Fay, defence attorney. “No one with a heart could hear that and be unmoved. Any of us that are parents, just, it strikes right to the heart.”

On Tuesday morning, Jordan Segura's mother spoke through her tears and said her son was "affectionately known as baby until he was three-years-old' and that he did nice things for others every day and "gave away kindness for free."

His brother, Julian, also spoke and said Jordan was "a mentor and leader' and that he was the kind of guy "to light up a room with his smile and laughter."

Lawrence Hong's parents and brother, Miles, wore T-shirts with his picture on the front to court and described him as having a pure heart and having an interest in becoming a city builder.

Kaiti Perras' older sister, Nicky, thanked the court for allowing the families to speak about the victims and said Kaiti was strong willed and stubborn and that she "never gave up to be her best self."

Josh Hunter's sister Michaela wiped away tears as she talked about her brother saying "I was lucky to have the big brother I did." His mother said she misses the daily things and that Josh was a good hugger.

Ronda-Lee Rathwell, Zack's mother, told the court that he was "witty and chatty, determined and fair, loving and caring," and that he will be remembered for the life he lived saying that "he flourished at ACAD in his first and only year."

De grood sat in the prisoner’s box with a blank look on his face as he listened to the families of the victims.

“My client is receiving medications and as a result of those medications, he may not react in the way people would hope to see him react and I would only hope that people appreciate that what they see is not as a result of the way my client is but the kind of treatment he is receiving,” said Fay.

Fay says the proceedings are also hard on de Grood’s parents, Doug and Susan.

“They’re hearts have gone out to the families and friends of the deceased from the very beginning in this, they feel their loss, so it’s very difficult for them.”

The case was adjourned for the day just after noon and Fay says evidence regarding de Grood's mental state will be presented on Wednesday.

“Tomorrow you can expect to hear some more evidence. You’ll hear from two psychiatrists, who’ve dealt with my client, and they’ll be able to give some more information,” said Fay. “The Crown and I are presenting it in a way that best facilitates this process so It’ll be, again, a little different procedurally but it will accomplish the goal that certainly I have.”

The trial is scheduled to last about two weeks

For the latest on the de Grood trial, follow Ina Sidhu and Jordan Kanygin on twitter

(With files from The Canadian Press, CTV Alberta Bureau Chief Janet Dirks, and CTV Calgary’s Ina Sidhu)

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