File photo - A screen displays the Instagram logo. (REUTERS/Lucas Jackson)

While the sheer popularity of Facebook continues to make it the most fruitful social media platform for cops hunting down criminals, Instagram, too, is becoming increasingly useful thanks to its steadily growing pool of users, ne'er-do-wells among them.

In fact, San Francisco Police Department even has its own "Instagram officer," it was revealed recently. Eduard Ochoa is paid to scan the service day in, day out, keeping his eyes peeled for suspicious characters and criminal behavior, or for additional information on people of interest in connection with investigations already underway.

Related: In the online hunt for criminals, social media is the ultimate snitch

Ochoa's role was revealed in court filings published last week, though he's actually been engaged in tracking down criminals via Instagram for several years now.

"[Instagram] does help us tremendously in obtaining information from suspects," SFPD spokesperson Albie Esparza told MarketWatch this week. "They post pictures of illegal activity. Some criminals even brag about it."

Indeed, it's the temptation to brag on social media services that catches out so many criminals. One of Ochoa's recent successes was a 17-year-old minor whose gun-wielding Instagram photos led to charges of illegal firearms possession. It's not clear if it was the minor's "40glock-" username that first brought him to the attention of Ochoa, but it can't have helped.

Related: Man posts Instagram selfies with stolen good, gets arrested

The San Francisco Police Officer's Association recently praised the SFPD's Instagram officer, along with several of his cyber-sleuth co-workers, for carrying out an "extremely intensive investigation using the most modern techniques provided by our new electronic age" to locate a recent suspect involved in a shooting in the city. In another case a couple of years ago, the department managed to use Instagram images to match a weapon to a suspect and then track him down using selfies he'd posted.

Facebook, as already mentioned, still provides cops with the most leads when it comes to apprehending individuals for illegal behavior. Often, the culprits bring it upon themselves -- there was, for example, the guy who was arrested shortly after "liking" his own wanted ad, and a woman who was picked up by cops soon after posting a selfie wearing a recently stolen dress. And we mustn't forget the wanted guy who taunted cops on Facebook with a "catch me if you can" message before being arrested the very next day.