Story highlights Federal agents raced against clock trying to save girl in internet image

Using high-tech kit, they found a single clue, tracked it down and saved the girl

Homeland Security Investigations use combination of computers and old fashioned detective work

In 2013, HSI agents rescued 337 children and took 964 alleged predators off the streets

Federal agents watched in horror as an unknown male in an internet photo appealed for stomach-churning advice -- how to rape the child beside him.

The girl was in pajamas and the man appeared intent on abusing her sometime soon.

Homeland Security agents knew they were in a race against time to save the girl.

In a narrow, windowless office outside Washington, DC, Special Agent Jim Cole sits at a bank of computer screens. The room is modest but the technology Cole is using is second to none.

He showed CNN's Freedom Project how Homeland Security Investigations agents chase down child pornographers. The tone in his voice changes when he begins to tell us about the 11-year-old girl and the special case, which the agency has termed "Sunflower."

"This Sunflower series [of photos] was being posted by an individual who was looking for information on how best to rape this little girl and get away with it."

Cole, who has daughters of his own, says he began scanning the photos being posted online for any clues that might give away their location. And he knew, he didn't have much time.

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"The advice he was getting online ranged from drugging her to brutally attacking her," says Cole. "It was progressing so we were extremely concerned for her welfare."

The agent noticed a blurry highway road sign in the window. It was his first, and best, clue. He and his colleagues set to work.

The road sign looked like a sunflower logo -- a clue that led agents to Kansas where the sunflower is the state flower.

And the first number on the sign was surely a 2. But the other numbers were too blurred to be sure which road it was.

"We began looking at the road sign. It really looked to most of us like a highway 203, and there was a highway 203 in Kansas, [but] when we got there, got off the plane the agent from Kansas said "it's not 203, we just drove the whole highway, the sign's not there.""

So Cole and the other agents got back on the road and started driving every highway in Kansas that starts with a 2.

"At the very end of the highway where it teed into another highway, we found the sign. I jumped out of the vehicle on a very busy highway and almost got hit by a car."

Knowing the approximate location, Cole called the local sheriff's department, who recognized a backyard swimming pool in another one of the photos.

They conducted a raid; arresting the suspect before the exploitation could escalate to the point of rape.

"When we went in that morning, [the 11-year-old girl] was still wearing those same pajamas as depicted in the images."

An ICE spokeswoman said the girl is now safe and living with her parents. She added the suspect turned out to also be a minor --16 years old -- who pleaded guilty and was sentenced to serve 48 months in a juvenile facility.

Former ICE Director John Morton, speaking in January, touted the success of this raid and subsequent ones -- named Operation Sunflower after the Kansas case -- that rescued 123 children, reminded Americans that while there was good news to report, the dangers that children face online and elsewhere remain.

"As satisfying as the arrests in Operation Sunflower have been, today is obviously a day of mixed emotions because this operation is ultimately a tale of the perverse, pervasive and violent exploitation of children - very young children to satisfy the dark pleasures of a group of twisted adults," said Morton.

"Sadly, some of the children were very young. For example, some of the children we rescued were between the ages of two and three. Nine children were between the ages of four and six."

Already in the first six months of 2013, HSI agents have rescued 337 child victims, and they've taken 964 alleged child predators off the street.