(CNN) -- The horseback riders braving the rugged Idaho wilderness came upon the older man and younger female and sized them up on the spot: A pair of greenhorns, square pegs in hard country.
"They just really didn't fit very well," rider Mark John said Monday on CNN's "New Day." "The expressions on their face, their demeanor, just didn't fit that country."
After the riders got home, they turned on the TV and realized they had stumbled upon the objects of an intense manhunt across the West. An image of the girl was in an Amber Alert, the child abduction alert system.
She turned out to be 16-year-old Hannah Anderson, the teen taken captive by a family friend, James DiMaggio. Troopers from California to Idaho had been hunting them down for about a week.
The riders contacted Idaho state police and their tip over the weekend sent FBI agents swarming to the camping spot outside Cascade, in central Idaho.
Hannah was rescued. DiMaggio died in a confrontation with an FBI agent.
Out in the wild, the four riders, Mark and Christa John and Mike and Mary Young, briefly interacted with the pair. Their presence just didn't seem to add up, the Johns said.
They used brand-new camping equipment, and the girl wore pajama-like bottoms in a place that required different clothes, the riders said over the weekend. The look on her face? Scared, Mike Young said.
"They weren't dressed for the country or the area and then as we rode further on, we encountered the tent that they had set up, which was totally out of place. it was way on top of a mountain, looked like it would make a real good lightning rod. So we was discussing the fact that they didn't fit there, that something was wrong," John told "New Day."
Christa John, also interviewed on "New Day," said she was inclined to go over to the girl and see if she needed help. But she refrained.
"Mark says, you know, maybe he had a feeling being in law enforcement for all those years and in the military, he had a feeling I shouldn't maybe do that," she said. "I did want to make contact with her. In retrospect, I'm glad that I didn't because that could have turned out terribly wrong for all of us."
However, she did speak to the man.
"I did talk to him about why he was there in this far-out place and he said she got to pick where we went last year. She wanted to go to Los Angeles and to Hollywood so this year it was my turn and that was a good explanation for me," she said.
The riders underscored the importance of Amber Alerts and what law enforcement always preaches to citizens: Be vigilant.
"People need to be aware and observant," Mary Young said on "New Day." "Otherwise we would have missed turning in that information."
Christa John says it's better to call law enforcement and "be wrong about the situation than not make it at all." She said everyone has a "God-given feeling" when they sense wrongdoing.
"Act on it," she said. "You are usually right."