SAN BERNARDINO (CBSLA.com) — The Marine killed outside a strip club in San Bernardino on Sunday has been identified as Pvt. 1st Class Douglas R. Rivasrauda.

The 20-year-old had been in the service for about six months. According to his Facebook page, he was also mixed-martial arts fighter.

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His mother posted on Facebook, saying: Sunday was the most difficult day of her life, and she doesn’t want to accept that he’s gone.

“I think that it’s unfortunate that his parents or family probably worried about him getting injured in battle. And instead, he was victimized in the city of San Bernardino,” said Eileen Hards of the San Bernardino Police Department.

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The city has had 19 homicides this year, a 30-percent jump from last year.

Investigators said they have security video of the killing and are talking to witnesses. No one from Flesh Club on Hospitality Lane would speak to CBS2/KCAL9’s Adrianna Weingold.

Shikeara Bryant of Rialto said the bouncers are usually on top of any incidents that begin to happen. “I’ve been there plenty of times. I just can’t believe it. When things get out of control, the security, the bouncers usually handle it. So, for somebody to get killed, it’s crazy.”

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Anyone with information about this case is asked to call the San Bernardino Police Department.