The grand jury indicted Christina Regusters, 20, on involuntary deviant sexual intercourse and aggravated assault charges, the Philadelphia Inquirer reported.
"These charges are very serious and very meaningful," said Thomas R. Kline, the lawyer representing the victim's mother. "These charges would put her away for the rest of her life," Kline said.
Regusters allegedly dressed in Muslim clothing to pose as the victim's mother and then abducted the young girl from a West Philadelphia school in January.
She allegedly sexually assaulted the victim in a nearby house, the Inquirer reported.
The girl was found in a park the next day wearing only a T-shirt.
Regusters was arrested Feb. 14, but the district attorney chose to use the grand jury to allow witnesses to testify in private.
The lawyer representing Regusters, W. Fred Harrison Jr., said his client intends to plead not guilty.