The unknown attacker broke into the girl's home early Saturday, found the girl in her bedroom and took her from her bed, The Washington Post reported.
Police say the suspect took the girl to a nearby location and assaulted her. They are unsure where she was taken or how she made it home.
The parents were unaware of the abduction until the girl returned home at 4 a.m. and told them.
The child was taken to the hospital for non-life-threatening injuries. It is unclear whether the girl was sexually assaulted.
"We haven't connected this to anything at this point. We've seen nothing else similar in this area," police officer Don Gotthardt said. "The frustrating thing is there is no further description of the suspect at this time."
Neighbors were surprised by the incident, saying nothing like that has happened in the area before.
"They play a lot in our front yard, and we were never worried about that," said a neighbor whose children play with the girl. "It's really surprising, because we've never heard of anything like that happening here."