A security officer at South Texas College is issuing a warning to parents after seven men were arrested for attempting to meet with underage girls for sex.

Investigators say the men used online chat applications, like WhatsApp and Discord, to find the girls. 

"I think you have to establish communication with your teenager," STC Chief Information Security Officer Luis Gonzalez said.

For Gonzalez, keeping kids safe online boils down to habits and talking with your kids.

"Knowing who they're communicating with," Gonzalez said.

He calls it a reality check.

The Edinburg Police Department announced they led an undercover operation that ended with the arrests of seven men.

RELATED STORY: Edinburg police arrest seven men in undercover child sex sting operation

Police say they were talking online with who they thought was a 16-year-old girl for sex when it was actually an Edinburg police investigator all along.

Police say the men were arrested when they showed up at an undisclosed location to meet with the teen. Records obtained by Channel 5 News state one of the men offered to pay $300 for sex.

"These men preyed on what they believed to be minor children. I urge parents to know what your children are doing online, know who they're communicating with, know what presence they have on social media," Edinburg Police Chief Jaime Ayala said.

Experts say it also starts with setting limits.

"You might go to sleep, you might have your house locked, you might have the alarm and everything, but they might be in their room, and they might be communicating with these type of bad actors," Gonzalez said.

Gonzalez recommends children and teens not have their phones or any device they can use to communicate online in their room.

"I don't see anything bad going through my kids' phone whenever it's necessary, or I think something odd is happening," Gonzalez said.

Gonzalez said staying aware of any changes in behaviors, such as trying to hide their screens, can be a clue for parents.

He said to be honest with your kids about the risk of using social media.

"Talking to them about this particular story, sitting down with them, telling them what are the dangers," Gonzalez said.

The seven men are facing charges that include coercion, enticement of a minor and online solicitation among other charges. All but one are being held in federal custody.

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