A fatality inquiry into the death of a 17-year-old who was gunned down by police got underway at the Edmonton Law Courts Monday.

Cyrus Green was killed after being shot three times in the chest by an Edmonton police officer on February 5, 2011.

The officer was responding to a robbery call at the Coliseum LRT station on a Saturday morning.

Three suspects, including Green, had fled the scene.

In court Monday, the officer who killed Green spoke.

EPS Cst. Jack Redlick was emotional when describing how the teen “came at him” that night with a bat and knife, forcing him to shoot.

Ten months after the incident, an investigation by the Alberta Serious Incident Response Team (ASIRT) found the officer’s actions were justified.

The investigation found that Green was carrying an aluminum bat and a four-inch knife at the time.

When told to lower his weapons, investigators say he raised them, and shouted "You're going to have to shoot me first".

The medical examiner found that Green was under the influence of alcohol and marijuana.

Six witnesses are scheduled to appear during the three-day inquiry, including other officers who were present when the shooting occurred.

ASIRT will appear in court Tuesday.

With files from Brenna Rose and Julia Parrish