Hunters appear to have stumbled upon the remains of the two missing cousins, Lyric and Elizabeth.
Updating...Note the quote from July claiming the family had not cooperated.
"Right now, it's looking like the outcome was not the one that we wanted," Abben said at a news conference in Evansdale, Iowa.
The girls were last seen by their grandmother on July 13 when they left for a bike ride. The girls' bicycles and a purse were found near Meyers Lake hours after they were reported missing.
A search of the 25-acre lake in July turned up nothing, and authorities said they believed the cousins were abducted.
"Cooperation with law enforcement is the key factor in discovering the whereabouts of Lyric and Elizabeth," FBI spokeswoman Sandy Breault said in July. "Unfortunately, in this case, law enforcement has not received total cooperation from all family and close friends," she said.
Abben said the investigation is ongoing, and he thanked the public and the media for their assistance and support