Philadelphia police say a 14-year-old boy is a serial rapist.

The boy, who is in custody, is already implicated in half a dozen attacks on teenage girls and women up to the age of 32. Police say they're using his DNA to see if it matches evidence from any other sexual assaults.

Some of the attacks were close to his home in the Nicetown neighborhood of Philadelphia. Others were in Olney, Mount Airy and West Philadelphia.

According to an article in the Philadelphia Daily News, police sources said his spree started during the summer and recently ended as victims kept telling cops their attacker was a young boy with acne.

The boy's grandfather spoke to the Philadelphia Daily News, but would not give his name.

"All I know is what I have been told and I don't believe it," the boy's grandfather told the Philadelphia Daily News. He added that his grandson had not been home "for a while."

The article says the boy attends Olney High School on Duncannon Avenue.

The Philadelphia Daily News said it withheld the boy's name because of his age.

The AP and the Philadelphia Daily News contributed to this article.