East-metro law enforcement leaders, sounding an alarm over the growing number of predatory internet crimes, issued an appeal Thursday to parents to step up inspections of their children’s activities on social media.

The prosecutors and sheriffs of Ramsey, Washington and Dakota counties said technology has opened dark corners of the internet to more and more children whose vulnerability is being exploited for sex and for money.

“Every parent in America needs to be aware of social media. There are a lot of parents, unfortunately, who are clueless,” said Dakota County Attorney James Backstrom.

Their comments came during a seminar in Stillwater where investigators and youth advocates talked about how predators troll for children online, what law enforcement is doing about that, and how communities and families can work together to protect themselves.

“The largest harm kids face is that parents don’t understand how apps are gateways to risk-taking behaviors,” said Jessica Wong, a teen advocate with the Hazelden Betty Ford Foundation.

Wong said good things also happen with technology, and today’s children will use it for tomorrow’s advances in medicine, education and employment. But she added that too many kids today are handed $700 devices with no discussions about safety and often little parental awareness about who they’re communicating with and what they’re doing.

Recent high-profile crimes against children in the metro area include the case of Cheyenne Cody Vedaa Foster, a 19-year-old Washington state man who found a 13-year-old Lake Elmo girl through the social media app Kik. He commanded her to abuse herself sexually over several ensuing months. In June, Foster received double the maximum sentence for what amounted to internet rape and was sent to prison for 29 years.

Phone applications like Kik can be difficult for parents to understand, especially as technology produces ever-newer interactive apps, and kids — not adults — know them best. Among these popular apps are Whisper, WhatsApp, Vine, YouNow, Periscope, Triller and another named High There! — billed as a dating app for people who want to smoke pot.

“You can say whatever’s on your mind and you stay anonymous ... and no one will ever judge you,” a girl said in a online promotion for After School, another app mentioned Thursday.

“We’ve moved so quickly,” said Alison Feigh, program manager of the Jacob Wetterling Resource Center. “The tools are out there, they’re instant and young people need the adults in their lives to help them navigate that technology safely.”

Feigh, who was a presenter at Thursday’s seminar, also said that law enforcement authorities, parents and communities need to “raise up youth leaders” to help find solutions.

“They’re smarter than we think they are,” she said.

Washington County Sheriff Bill Hutton said that internet crime has become a daily occurrence and that many of his phone calls come from parents concerned over what their children are doing online.

Sheriff Tim Leslie, of Dakota County, said parents need to recognize that smartphones offer many good qualities but that they’re also unregulated gateways to activities such as viewing pornography and learning how to snort cocaine.

“We’re lagging in law enforcement. We need to get the word out,” Leslie said. To do that, the Dakota County Sheriff’s Office has joined area police departments to share resources in hopes of staying ahead of advances in technology, he said.

Dave Pinto, an assistant Ramsey County attorney and a state legislator, said 1,700 Minnesota law enforcement officers have been trained to detect internet crimes, as have 5,000 other people who work with vulnerable youth.

“The more I learn, the more I see it everywhere,” said Washington County Attorney Pete Orput. “Predators prey on the trust that our kids share online in what is otherwise a positive place to exchange personal information.”