Omar Mateen was born in Queens in 1986 to Afghan parents. He moved to Florida with his family in 1991 and spent his early years in the Port St. Lucie area on the state’s east coast. In both elementary and middle school, his teachers described him as often being unable to focus or control himself in class. As a young man, Mr. Mateen became interested in a career in law enforcement and earned an associate degree in criminal justice technology from Indian River State College in 2006.

As investigators comb through his past to glean an understanding of the young man whose attack on the Pulse nightclub in Orlando killed 49 people and wounded 53 others, a portrait of a complicated childhood and young adulthood is emerging. These documents offer a glimpse into Mr. Mateen’s life. Related Article

