MORENO VALLEY (CBS) — A volunteer police patrol interrupted a sexual assault at a Moreno Valley park after a woman was forced out of her friend’s car at gunpoint and raped.

Derek Anthony Banks III, 18, ran from the sheriff’s volunteer who shined a spotlight on the sexual assault, according to a department report. He was arrested for rape, suspicion of rape, suspicion of robbery, kidnapping, and assault with intent to commit rape.

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The woman and a male friend were accosted just before 8 p.m. Friday at El Potrero Park, in the 16900 block of Lasselle Street, according to Riverside County Sheriff’s Sgt. Dave Lelevier.

Banks allegedly threatened to shoot the couple and demanded money, before sexually assaulting the woman at gunpoint

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The suspect ran out of the park as the volunteer radioed for backup. Deputies found him a short time later in the 16000 block of Calle Pinata, just north of the park, Lelevier said.

While searching the area, deputies found a semi-automatic handgun and some of the victims’ clothing and property, as well as additional evidence that officials say links Banks to the crime.

Banks was being held in lieu of $50,000 bail.

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