The Edmonton police constable who shot Cyrus Green three years ago told a fatality inquiry on Monday that he fired his gun as the teen ran towards him holding a knife “like a spear.”

"I remember seeing the shiny silver of the knife,” Const. Jack Redlick testified.

“The blade looked huge. It looked like a big kitchen knife, in essence."

Redlick says he then fired three shots at Green, 17, near the Coliseum LRT station on Feb. 4, 2011.

The teenager later died in hospital of multiple gunshot wounds..

Redlick told the inquiry that he and two other officers were called to a robbery inside the Coliseum LRT station.

An officer who was already at the scene radioed that he had been challenged by someone carrying a bat and a knife and was chasing the suspect on foot.

When Redlick arrived at the scene in his police cruiser, Green was running towards him.

"Stop. Drop the bat,” Redlick recalled shouting at the teen.

"There was anger in his face. He started to spring towards me. Raised the knife. Pure anger."

"You're going to have to [expletive] shoot me,” Redlick says the teen replied. That’s when Green ran at him with the knife.

Redlick fired his gun three times. But Green kept coming towards him.

"I thought I'm going to get stabbed in the throat here,” he told the inquiry as he fought back tears.

The teenager then fell to the ground in front of him. Redlick put handcuffs on Green and rolled him over.

Redlick says the teen then gave a “hollow kind of gasp” and said “shoot me again."

Carol Green, the teen’s mother, said outside court that she doesn’t believe her son said those things.

“No. No. I raised him all my life,” she said. “And he was a very caring boy - like my baby right there.”

The Alberta Serious Incident Response Team (ASIRT) investigated the shooting and cleared Redlick of any wrongdoing after finding that he acted in self-defence.

The fatality inquiry is scheduled to take three days.

With files from the CBC's Janice Johnston