Police Arrest Miami Student for Posting Gun Photos Online Then Find Illicit Porn on His Phone

One Miami father told police he was worried about his son's disturbing posts with guns on Instagram and Snapchat following the massacre at Marjory Stoneman Douglas High School. So he gave investigators his son's smartphones — and along with gun photos, they found child porn, police say.

Early Friday, Miami-Dade Schools police jailed Sean Mesa, 18, a student at Dr. Michael Krop Senior High School, on charges of possessing child pornography, as well as improper display of a firearm, the Miami Herald reports.

Since Feb. 14's shooting in which Nikolas Cruz killed 17 people at his former high school with an AR-15 rifle, police have tightened responses to online threats. Before the shooting, Cruz had come to the attention of local and federal authorities for his disturbing online posts with threats and weapons — red flags that were never investigated.

Mesa came to the attention of U.S. Homeland Security Investigations' Violent Gang Task Force, which forwarded his Instagram and Snapchat photos "recklessly displaying firearms and pointing them at the camera," according to an arrest warrant.

Miami-Dade Schools Detective John Messenger went to Krop High School on Tuesday to "engage in a friendly conversation to understand what Sean Mesa's fascination with firearms was."

Mesa reportedly bristled, telling Messenger "he liked guns and it was his right to post on social media whatever he wished." But Mesa's father agreed to give police Mesa's two phones, which the Secret Service examined and found a video of what appeared to be a child under the age of 10 being sexually abused, according to the warrant.

The video had been sent to two others in a group chat, the warrant said.

Using other devices, Mesa continued posting on Snapchat. Another post showed a pistol on his lap with the caption: "now they watching so I ain't stopping."

"The latest Snapchat photos have students and staff at Dr. Michael Krop Senior High alarmed and afraid," according to the warrant.

Mesa's father reported his son after growing increasingly worried about his son's online behavior. Authorities are likely taking online threats such as Mesa's more seriously after Cruz's went unpunished — an ultimately deadly mistake.

In an effort to deal with Cruz's frequent violent outbursts and online threats, Cruz was toggled between different schools in the Broward County School District — six in three years. Many say local authorities had more than ample opportunities to address Cruz's behavior, as multiple 911 calls were made about him. Even the FBI was alerted to his online behavior when he left a comment on a YouTube video that said "I'm going to be a professional school shooter."

Cruz frequently posted photos with his guns, of which he had at least 10 — and threatened other students, who said they weren't surprised to learn that Cruz was the shooter.

On Sunday, a 13-year-old boy was arrested in Missouri after making a video threatening to shoot up the school with an AK-47. And a day after the Stoneman Douglas shooting, a sixth-grade girl was arrested in a town just half an hour away from where the massacre took place after she wrote a note threatening to bring a gun to school and kill "kids and teachers."