Newly obtained information from the Orlando nightclub shooter's school and work records show he caused trouble at an early age and, as an adult, became a proficient marksman with consistently high scores in tests.
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As far back as 1992, when he was in elementary school, teachers described Omar Mateen as a “disruptive influence” or “classroom disruption” and cited him for “repeat misconduct,” using profanity and even striking another student, according to St. Lucie County school records obtained by ABC News.
He had two marks on the records during the 1992-1993 school year. Between 1996 and 1998, when Mateen was in 5th through 7th grades, the record is filled with incidents and complaints from teachers and school officials -- more than 30 of them. He left St. Lucie County schools in 1999 and transferred to another district in 8th grade.
In a letter sent to Mateen’s father in 1999, a Southport Middle School official wrote, “Omar’s attitude and inability to show self-control in the classroom create distractions and become a main source of difficulty for him.”
Mateen, who killed 49 people at Pulse nightclub in the early morning hours of Sunday, June 12 and died in a firefight with police afterwards, became a security guard as an adult.
The state kept records associated with his annual security guard license renewal, which including scores from marksmanship tests at a shooting range. All of his scores since 2008, except for one year, were at or near the maximum.
On earlier tests, he scored extremely close to the highest possible of 240. His scores dropped slightly as time progressed, but still remained above 200.
To qualify, he fired at least 48 rounds while an instructor tested his stance, grip and sighting among other factors.
Proficiency was demonstrated with both a revolver and semi-automatic pistol -- the same caliber as one of the weapons that he was found with after the deadly nightclub shooting.
His security guard license was briefly suspended in 2014 over a paperwork problem, which was quickly corrected.
There is no record of a criminal history with the Florida Department of Law Enforcement. On other state applications, Mateen had indicated the record was sealed or expunged.