ST. ROSE - A man shot and killed his 21-year-old son after he showed up at his parents' house with a gun and bulletproof vest.  

The St. Charles Parish Sheriff's Office said the shooting happened Tuesday after an argument erupted between the 21-year-old and his mother at the home in St. Rose. 

Deputies said the confrontation escalated after his father arrived. The sheriff's office said the son then drew a handgun, prompting the father to pull out his own weapon and shoot. 

The 21-year-old, whose identity has not been released, died from his injuries.

According to the sheriff's office, the son had a history of "unstable and violent" behavior and previously underwent mental health treatment. 

Investigators said the incident was unrelated to another shooting that happened in the same area a day earlier.