Harrisburg - Investigators have received a significant number of tips related to the case of a boy allegedly raped by several men, including one who would dress in a fox costume before attacking him, Pennsylvania's top prosecutors said."We have reason to believe that there may be other perpetrators, there may be other victims, which is why we spoke out publicly about this the other day," state Attorney General Josh Shapiro said Thursday.He said the calls have come in to a tip line announced over the weekend, as authorities disclosed that five people had been charged in the investigation."We've seen a significant spike in the number of tips that this office received and we are evaluating those tips," Shapiro said, declining to elaborate.Court records indicate the boy, now 15 years old, had to dress as "Tony the Tiger" at fetish parties in the Philadelphia suburbs where some of the attacks occurred.Three men are accused of child rape. A fourth is accused of trying to have sex with minors through online contact. Details about the fifth arrest, a Virginia man, were not immediately available.Allegations deniedAuthorities said the case began with the arrest of Jeffrey A Harvey, 40, of West Wyoming, Pennsylvania, last summer on charges he tried to have sex with someone he met online that he thought was a 13-year-old boy. The online person was an investigator with Shapiro's office.Harvey gave detectives cellphone texts he exchanged with David R Parker, 38, of Saylorsburg, in which Harvey expressed his desire to have sex with Parker and the boy victim, police said. Parker was arrested the next day.Harvey's lawyer, John Notarianni, said on Thursday that Harvey remains jailed and is "denying all allegations, at this point". Harvey is not charged with any crime related to the child victim.Police said Parker said he fondled the boy when he was 1 to 3 years old.The boy told investigators Parker molested him on multiple occasions in Schuylkill County before he was age 13 and, according to a search warrant affidavit, "would take him to homes or apartments where ... other adults would touch (him) in a sexual way".Parker's lawyer did not return a phone message seeking comment.The boy told investigators in October that Craig Michael Knox, 35, of Henrico, Virginia, had molested him at a home in Pittston.Suspect claims he was also abusedKnox told investigators that Parker encouraged him to "have at it" with the boy, and that Knox sexually abused the child in an upstairs bedroom, after which Parker also forced the child to perform a sexual act, police said."Knox stated that during this time the victim appeared embarrassed and looked at the floor as he did what he was instructed to do," police wrote.Knox was charged in November. A public defender listed on Knox's online court document declined comment.On January 20, the boy told an investigator that Parker, himself a "furry", took him in 2009 to the Quakertown home of Kenneth C Fenske, 57, who on several occasions would remove his fox costume before raping him, police said.Fenske was charged on Friday with child rape and related offenses. He did not have a lawyer listed in court records, and he did not return messages left on his home and cellular phones.The victim is now is in foster care and has been receiving therapy.