(CNN) -- The search for fugitive James DiMaggio and the 16-year-old girl he is suspected of kidnapping forges ahead, focusing on a 300-square-mile area of rough terrain in Idaho.
Some 150 law enforcement personnel were in the area to search for the missing girl and her alleged captor, said Andrea Dearden, spokeswoman for the Ada County Sheriff's Office. That number could increase to 200 on Saturday.
Authorities are posted at all the exits from the area where the car was found, she said.
A tip from earlier this week about a possible sighting resulted in the intense focus on an area of wilderness near the town of Cascade.
The increased number of searchers comes as the Sheriff's Department in San Diego County confirmed that 8-year-old Ethan Anderson perished in a fire at DiMaggio's house on August 4.
The body of Ethan's mother, Christina Anderson, had been identified earlier as a second victim of the house fire.
There was a likelihood from the beginning that one of the remains found in the house were Ethan, but it took a DNA analysis of bone marrow to confirm it.
DiMaggio is suspected of killing Christina and Ethan Anderson and kidnapping Hannah. The search is now focused on the rugged mountain area in central Idaho where the suspect's car was discovered Friday.
Hannah Anderson was last seen August 3 at her cheerleading practice. Relatives reported the mother and children missing the next day.
DiMaggio's car was found hidden by brush Friday, with its license plates removed, in the River of No Return wilderness area, about 15 miles outside Cascade, Idaho.
Witness: DiMaggio had crush
A friend of Hannah Anderson on Saturday provided a clearer picture of the relationship between DiMaggio and the teen.
Marissa Chavez told CNN that she was in a car with Hannah and DiMaggio a few months ago when the 40-year-old told Hannah he had a crush on her.
He followed it up by saying if he was her age, he would date Hannah, Chavez said.
Hannah was unnerved by the comments, but did not tell her mother because she did not want to ruin the close relationship that her parents had with DiMaggio, Chavez said.
After that, however, Hannah did not want to be alone with DiMaggio, Chavez said.
In an earlier episode, Chavez recalled a trip that DiMaggio and Hannah took to Hollywood. The trip was supposed to be for one week, but Hannah told Chavez that they came back after two days because DiMaggio was upset that she wasn't paying enough attention to him.
"I don't think she would have gone willingly with him at all," she said.
Focusing the search
The suspect's car was found after a man on horseback reported that he had a brief conversation with two campers in the Idaho wilderness on Wednesday. The rider's realization later that he may have been talking to DiMaggio and his alleged teenage captive has been the biggest break in the search yet.
The horseback rider saw the man and girl Wednesday and struck up a brief conversation with them, Dearden said Friday.
He was not aware of the manhunt at the time, but he called the Amber Alert tip line after he saw a news account that night and realized the pair matched the description of DiMaggio and Hannah Anderson, she said.
The rider's impression of the pair was "it seemed odd but nothing as alarming," Dearden said.
"They did speak and exchange pleasantries. I don't think there was a lot of information exchanged," she said. "He left the conversation believing they were camping in the area."
The rider said the man and girl were on foot, hiking with camping gear, Dearden said.
Dearden appeared to be correcting authorities' earlier reports that the suspect and girl were spotted by more than one horseback rider.
Investigators set up checkpoints where DiMaggio and Hannah were believed to be traveling, Dearden said.
DiMaggio's vehicle will be examined by bomb and arson technicians to ensure it's not rigged with explosives. The San Diego County Sheriff's Department has said evidence found at the burned house indicates that explosives may be in the car.
DiMaggio was a close friend of the Anderson family, and father Brett Anderson has appealed to DiMaggio to let his daughter go.
CNN's Michael Martinez and AnneClaire Stapleton contributed to this report.
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