In May last year, a 15-year-old high school student befriended a 16-year-old Dallas boy on social media.

Her friendship blossomed and they started sending sexual photos of themselves, commonly called sexting.

The boy also was getting lots of photos from girls in other states. Only, he wasn’t a 16-year-old Dallas kid. He was a 42-year-old married man.

A ripple of “eww”s reverberated through a room of about 150 students at Veterans Memorial High School when federal prosecutor Hugo Martinez told the story Monday.

Martinez recently prosecuted Daniel Heidemann, who in August pleaded guilty to sexual exploitation of a child and is awaiting a sentencing hearing in November. Heidemann faces up to 30 years in prison and a maximum $250,000 fine.

The biggest problem right now, and a large portion of Martinez’s cases, is adults posing as children online and in cellphone apps, he said. Martinez speaks to high school students to warn them of online predators.

“There are actually people out there that all they do is troll online looking for young men and women like yourselves and try to lure them and trick them into sending photographs of themselves,” he said.

The same threats can exist with the high school boyfriend or girlfriend they see everyday and trust, Martinez told the students. A boyfriend might forward photos of his girlfriend after a breakup, for example. That’s distribution of child pornography and can land the distributor in prison for 20 years. Martinez described several scenarios and explained the possible federal charges for each.

The best way for students to protect themselves is to have high self-esteem and respect themselves, Martinez said.

“The reality is if anybody asks you for a naked picture of yourself, that person is not a person you need to be with,” he said. “Because anybody who respects you or really loves you isn’t going to ask for something like that, is going to have more respect for you and your body.”

And if somebody sends an unsolicited photo, Martinez’s advice is to report it to a parent or teacher.

Caller Times: Prosecutor talks to students about “sexting”, online predators