(CNN) -- The parents of a 15-year-old girl who was gang-raped on a California high school campus urged the community Saturday to channel its anger over the event "through positive action," according to a pastor.
At a Saturday community event at the campus where the attack took place, the Rev. Jim Wheeler, who said he was the family's pastor at First Presbyterian Church in Richmond, read a statement from the teenager's parents.
"Stop the violence," Wheeler read. "Please do not respond to this tragic event by promoting hatred or by causing more pain. We've had enough violence already in this place."
Police say as many as 10 people were involved in the rape on October 24 in a dimly lit back alley outside Richmond High School, where a homecoming dance was taking place.
Another 10 people watched the attack without calling 911, police say.
Five people have been arrested in connection with the attack.
A sixth person who was arrested is expected to be freed because of insufficient evidence, CNN affiliate KGO reported.
Authorities say the attack lasted for more than two hours. The victim, who was taken to a hospital in critical condition, was released Wednesday.
The parents' statement urged the community to work to ensure that such an attack never happens again.
"If you need to express your outrage, please channel your anger through positive action," they said, according to Wheeler.
"Volunteer at a school. Go help a neighbor. Be courageous in speaking the truth and in holding people accountable. Work toward changing the atmosphere in our schools and in this community so that this kind of thing never happens again.
"Please do not let this happen again."