It happened around 10:00 p.m. at a home on South Harlan Street, near Alameda Avenue.
Lakewood police say a woman was visiting a male friend at his house when her ex-boyfriend showed up and a fight ensued.
Police say the woman's friend then shot the ex-boyfriend an unknown number of times, killing him. The friend is being questioned but no arrests have been made.
Lakewood police say the "Make my Day" law, which gives homeowners the right to use deadly force, will be considered in this incident.
Police say it's too early to say if the homeowner will be charged.
The names involved have not been released.
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