**UPDATE** Wed, 12PM EST
A seventh person has been arrested in a gang rape on a high school campus in northern California, police said Tuesday.
Richmond Police Lt. Mark Gagan did not identify the suspect. Of those arrested so far, one was released for lack of evidence.
Police say as many as 10 people were involved in the rape October 24 in a dimly lit alley outside Richmond High School, where a homecoming dance was taking place.
Another 10 people watched the attack without calling 911, police say.
Authorities say the attack lasted for more than two hours. The victim was taken to the hospital in critical condition, and was released Wednesday.
Richmond police are ponying up a $20,000 reward for information leading to arrests. "The $20,000 award is for information leading to the arrest and conviction of anyone involved in the attack," said. Lt. Mark Gagan. You can call reach the Richmond Police Department at 510-233-1214.
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ORIGINAL STORY
A 15 year-old Richmond High School student was gang raped by at least four different individuals while a crowd of 15 people, all males, watched for more than two hours as the annual homecoming dance was under way inside the school in San Francisco, California.
“Based on witness statements and suspect statements, and also physical evidence, we know that she was raped by at least four suspects committing multiple sex acts,” said Lt. Mark Gagan of the police department in Richmond, California.
“As people announced over time that this was going on, more people came to see, and some actually participated,” Gagan said. “We have checked Facebook and YouTube to try to find any revealing evidence. We’re looking in particular to see if anyone posted any video of the incident.”