The Florida Department of Law Enforcement and Indian River State College in Fort Pierce, Florida, have released several records connected with Mateen, potentially shedding some light into his life before authorities say he committed the worst mass shooting in U.S. history.
Mateen wrote that he had background in law enforcement working as a correctional officer trainee and security officer in 2006 and 2007. Mateen also wrote that he applied to become a Florida state trooper in 2011.
When he was a freshman in high school, Mateen was sent to an alternative school after he got into a fight with a fellow student, he wrote in a questionnaire for the Indian River State College Criminal Justice Training, which he filled out on Nov. 19, 2014. It is unclear what the fight was about.
In his employment history, Mateen, who said he had a degree in criminal justice from Indian River State College, wrote that he had worked at the Marin Correctional Institution in Indiantown, Florida as a correctional officer trainee from October 2006 to April 2007, and cited the reason for leaving as "probationary dismissal."
On the questionnaire, Mateen said that in 2006, he was on a "ridealong" with a police deputy in St. Lucie when the patrol car hydroplaned and "got wrapped around a tree."
Mateen checked "yes" to a question that asked if he had "ever been arrested, charged or received a notice or summons to appear, convicted, pled nolo contendere or pled guilty for any criminal violation or detained by ANY law enforcement agency." There was no further explanation on the form.
Mateen said he had some sort of criminal record sealed or expunged, but no explanation was provided as to what the record was.
Early Sunday, Mateen entered the Pulse nightclub in Orlando and began shooting at random with an AR-15 style gun, officials said. The ordeal lasted more than three hours and included a shootout with police and Mateen taking club-goers hostage. Mateen was shot and killed by police.
A marriage license shows that Mateen has been married to his wife, Noor Salman Mateen, since Sept. 29, 2011. Investigators are trying to determine if she knew something in advance about the attack. Noor Mateen claims she tried to talk her husband out of it, a law enforcement official told ABC News.
The marriage ceremony was performed in Berkeley, California, after the couple met online, a family member of Noor Mateen told ABC News. It is unclear on what website the couple met. Her parents were born in Palestine, the marriage license shows.