My 9-year-old was sent graphic photos by a stranger. The police told us it happened all the time.

Cavan Images/Getty Images My son called me in tears after receiving a text with a graphic photo. He had replied to a text from a stranger who was using a common phishing tactic. We contacted the police, who told us they couldn’t do anything but that this happened all the time.

When I saw an incoming call on my son’s Apple Watch during school hours, I knew something was up. In tears, he shared he’d been texted a graphic photo. The explicit image had left him distressed, rightfully so.

After a little prodding, I found out he’d responded to a message sent by someone from an unknown number. The text, which seemed harmless — “Hey, why haven’t I heard from you lately?” — turned out to be anything but.  My son told his teacher, who immediately took the watch and alerted the principal.

The local police were called, and I went to the school to meet them. But because the scammer hadn’t addressed my son by name, there wasn’t anything they could do, nor any way to prove that they knew they were scamming a child. Beyond blocking the number on his device and deleting the message, we had no recourse.

Most troubling, one of the officers said it happened all the time. What to do if your child is harassed by a scammerAccording to Erin Wilkey Oh, the content director of family and community engagement at Common Sense Media, what happened to my son was a form of phishing, when a sender baits someone into interacting with them. “Typically, phishing is an attempt to get someone to reveal private information, and then the thief will sell that information or use it to steal the victim’s identity,” Wilkey Oh said.

In my son’s case, the phishing was followed by harassment. Because my son’s father and I share parenting time, the watch was a good way for him to stay in touch with each of us. Though we’d implored him — on more than one occasion — never to respond to messages unless they’re from the few close friends and relatives on his contact list, the scammer still got to him.

 If a scammer strikes, make sure your child knows they’re not to blame — the bad actor is, said Devorah Heitner, who holds a doctorate in media studies and is the author of “Screenwise: Helping Kids Thrive (and Survive) in Their Digital World. ” She recommends that parents teach their kids to ask themselves, “Why is this unknown person contacting me out of the blue?”If someone claims to know you but you can’t verify the person’s identity, block them, or simply don’t respond to the message, Heitner said. How to avoid and respond to harassmentAs soon as kids start using devices, parents and caregivers should begin a dialogue about online harassment, Wilkey Oh said.

Regularly discuss online safety, responsible behavior, and how to respond to offensive comments. Help your kids set boundaries by encouraging them never to do anything that’s outside their comfort zones, such as sharing passwords or talking to strangers. Beyond that, we can help our kids learn to identify common tricks that scammers use to phish for information, Wilkey Oh added.

For example, a text is suspicious if the sender has an unknown number, the message sounds urgent, it doesn’t address your child by their name, sounds too good to be true, or conveys a sense of urgency.  And make sure your child feels safe confiding in a trusted adult — someone who has the authority to help them, Wilkey Oh said. Luckily, my son reached out to me right away and his teacher was able to intercept several explicit text messages that were sent in quick succession after the jarring photo.

I can’t imagine if he’d read them. More than that, it terrifies me to think an incident like this can — and does — happen so easily. Read the original article on Insider.