A case of a suspected pedophile convicted of grooming a child with the intent of committing a sexual offense has shed new light on sexual predators using Instagram to find potential victims.

According to the BBC, police in England arrested 39-year-old Dominic Nielen-Groen after he had driven over 160 miles to meet a 15-year-old girl he'd met and groomed on Instagram.

It's a common practice of pedophiles who use the social network to find teens and tweens and even children. It is also a tactic familiar to law enforcement and even Instagram.

Here is how it works:

Pedophiles will search for certain hashtags used by teens such as #teenmodel, #swimwear, #kissing. For those unfamiliar with how Instagram works, these hashtag searches will find every photo posted publicly using that hashtag. Hashtags are an important part of Instagram as they are how users find photographs of things they are interested in.

Pedophiles can then send a direct message or DM to the person posting the photo, or they can search through comments and likes left by other users. Direct messages can be sent to other users whether their Instagram account is set to private or not.

The Instagram user might be asked to share sexually suggestive photos and an offer of money. In the case in England, police said the 15-year-old had sent followers pictures of her body in exchange for money. Pedophiles have been known to use those photos as a way to extort more risqué pictures or even a meeting in person by threatening to share the pictures that were sent with the teen's parents and friends.

So even if your child's Instagram account is set to private know that the can still receive direct messages from strangers. Talk to your kids about the dangers of sharing too much on social media and communicating with strangers.

Instagram has blocked or restricted hashtags known to be used by pedophiles who had been swapping child porn with other users.