Husband, 45, claims he was acting in self-defense when he fatally shot his wife, 47, in the head because she was 'coming at him with a butcher's knife just weeks after he filed for divorce'

A Colorado man called 911 last week, telling a dispatcher that he shot and killed his wife after she attacked him with a butcher's knife. 

Scott Smith, 45, was arrested on suspicion of first-degree murder for the death of Kanokwan Smith, 45, in Littleton on November 1, but he was later let go after prosecutors concluded that they did not have sufficient evidence to pursue a criminal case against him. 

The victim's friends and co-workers reacted to the news with outrage, calling on the authorities to bring charges against Smith for her killing. 

Scott Smith, 45 , admitted last week to fatally shooting his wife, Kanokwan Smith, 47 , claiming  he did it in self-defense 

Scott summoned deputies to the couple's home in Littleton, Colorado , on November 1, telling a 911 deputy he had no choice but to shoot his wife 

Records indicate that Scott filed for divorce just a few weeks before the killing, The Denver Channel reported.   

The incident began unfolding on November 1, a Sunday, when Scott called 911, saying that he had 'no choice' but to kill his wife inside the family's home on West Ottawa Avenue.

'Yes, I had to,' he said on the call, according to Smith's arrest affidavit. 'Please send help right away.'

The document detailed how deputies with the Jefferson County Sheriff's Department found Kanokwan dead from a gunshot wound to the head. The married mom-of-one was purportedly shot from a very close range.

Under questioning, Scott claimed that his wife tried to kill him with a butcher's knife, so he shot her in self-defense.

Several of Kanokwan's friends, however, said they believe Scott murdered her.

Kanokwan, who was of Thai descent, worked three jobs to help support her 10-year-old daughter, including as a card dealer at the Ameristar Casino in Black Hawk, reported 9News.

Kanokwan, a mother-of-one, was found fatally shot in the head, purportedly from a close range, inside a small, cluttered room 

Her colleagues at the gambling establishment remembered Kanokwan, known to her friends as 'Noke,' as an exceptionally hard-working and gentle person.   

Her neighbor and friend Dominique Naylor said she had known Kanokwan for a decade and insisted that the woman was the kindest person she's ever met who was incapable of hurting anyone. She added that there is no doubt in her mind that Scott was at fault.

Kanokwan worked three jobs and was remembered by her friends as a kind and gentle person 

'He shouldn’t be out and he shouldn’t be free,' Naylor said of her friend's husband.  

A lawyer friend of the victim's who has reviewed the affidavit said that it makes no mention of any evidence suggesting a struggle inside the small, cluttered room where Kanokwan was shot, which raises red flags for him.

Another important detail, according to the friend, is that Scott was not injured and had no marks on him. 

A spokesperson for the Jefferson County District Attorney's Office said the investigation into the killing is active and ongoing.