Police will say that there was a fight and the victim was shot in the upper torso.
"To me, this is the most painful thing I could ever experience in my life," said Jessica Corde, the victim's mother.
Jessica Corde, surrounded by friends and family, pleaded for help. She wants to know what happened to her son, 18-year-old Marquis Leblanc.
"Please tell me who did this to my baby," said Corde.
A memorial on Virginia Avenue marks the spot where Leblanc was shot and killed Friday night. His mother says he and some friends went to a large house party. There were at least 200 people there. Pomona police say there was a fight at the party and it spilled outside.
Corde says eyewitnesses told her it was a violent attack.
"Twenty to 30 people beat him with boards and sticks and stomped him and kicked him until he was unconscious," said Corde. "And then when he lay unconscious, they walked up to him and shot him in the back of the head."
Residents suspect gangs, possibly Latinos and blacks at the party. Eyewitness News called Pomona police Monday a number of times. Police said the detectives working the case are off Monday and no one would talk to Eyewitness News.
Neighbors are frightened by all of this.
"It's just really sad," said neighbor Pat Bailey. "It's really sad that young people can't go out and have fun anymore."
Leblanc's mother says she's getting very few details and even though there were hundreds at the party, apparently no one is revealing much information.
"There is no reason that somebody has to die so violently and nobody ain't even showing up and stepping up," said Corde. "This is my place. This is my place to step up for my baby and I'm not going to stop. I'm not going to stop. I'm going to say it again. It's not a manhunt, it's a mom-hunt. Whoever you are, I'm coming after you.'
Pomona police are asking anyone with information about the shooting to call at (909) 620-2085.
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