The incident happened around 12:30 a.m. on the 13900 block of Iowa Street.
Police found the victims inside a garage. Four people were shot, including a juvenile.
One victim was pronounced dead at the scene and another victim died at an area hospital. The two injured victims were listed in serious condition.
According to initial investigation by Westminster police, the shooting may have been sparked by a verbal altercation. One man has been arrested, and investigators are still searching for one more suspect. Authorities say the incident is possibly gang related.
If you have any information about the shooting, you're urged to call Westminster police.