NORFOLK, Va. — They're the worst of the worst: criminals who exploit, entice and sexually abuse children.

There's a disturbing group of people out there targeting society's vulnerable youth, and investigators say with more people gaining access to the Internet every day, it's a growing problem.

At the Federal Bureau of Investigation, working in the unit that investigates these crimes is certainly a calling.

"They're very difficult crimes to investigate, so, it really does take someone who is special to dedicate their career to investigating these kinds of cases," FBI's spokeswoman for the Norfolk Field Office, Christina Pullen, told 13News Now.

There's a wide range of child sex crimes like pornography, trafficking, online enticement, and 'sextortion.'

The FBI says it often starts with a tip, either directly to authorities or a hub, like the National Center for Missing and Exploited Children. Then, the information is disseminated to federal, state and city-county agencies.

The groups are already working closely together.

In Norfolk, there's the Norfolk Child Exploitation Task Force. There's also the Southern Virginia Internet Crimes Against Children (ICAC) Task Force, which is part of a nationwide initiative.

At the FBI's Norfolk field office, dedicated police officers from local departments are sharing information and investigating crimes with agents, working side-by-side, every day.

"This lane is wide enough for everyone and we are all dedicated to work together to make sure that we protect children," Pullen said.

Certain factors, like crossing state lines or Internet usage, will determine the level of prosecution. 

Take the case of a Newport News soccer referee recently accused of 'sextortion.' Investigators say he used social media to coerce a Washington state girl into sending him explicit photos by threatening to kill himself.

The girl's mother contacted NCMEC.

When it comes to identifying a predator, Pullen said there is no particular profile to look for.

"That's the scary thing," Pullen said. "We see all walks of life - young, old, rich, poor, multi-ethnicity."

13News Now wanted to know what parents can do to prevent their child from becoming a victim.

"I think the best thing parents can do is engage with their children," Pullen said. "In terms of their Internet and social media activity, be a part of it. Be your child's friend on Instagram or Facebook."

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The FBI suggests going through your child's devices and knowing the apps they use, along with combing their friend's lists with them and asking how they know every single person.

"We want to make sure that kids are aware that not everyone on the internet is who they say they are," Pullen said.

It's also important to remind children that once they send something over the Internet or through text message, it's out there and it's not coming back.

Beyond that, the people who investigate these heinous crimes want kids to know it's not their fault.

"They're not alone. They're not in trouble and we want to help them," she said.

If you want to submit a tip about a possible child sex crime, you can reach out to NCMEC here. The FBI also accepts tips through 1-800-CALL-FBI or online.