A man is in custody following a fatal shooting at his ex-girlfriend's apartment building in Sioux Falls.

Authorities say the 38-year-old suspect killed 26-year-old Kaisean Marcell Tyler Monday shortly before 9 p.m. Police Lt. Nick Butler says the alleged shooter was arrested about 5 a.m. Tuesday.

Butler says police have not yet found the weapon used in the crime.

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A court affidavit says the suspect arrived at his former girlfriend's apartment to pick up some of his belongings and saw Tyler with the woman in her bedroom. Authorities say the two men exchanged punches and the ex-boyfriend pulled out a handgun and shot Tyler.

Pierre, Deadwood, Sioux Falls news

A Sioux Fall's man is in custody after killing a man who was at his ex-girlfriend's apartment.

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Tyler fell to the ground and the suspect fired three more rounds into the victim's back as his ex-girlfriend got on the floor and covered herself with a blanket, the Argus Leader reported citing the affidavit.

The woman told investigators that her ex-boyfriend once threatened to kill any man he saw at her with at her apartment.

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The shooting death is the third homicide of 2022 in Sioux Falls.