The suspected gunman, who fled the Gateway Center building in downtown Orlando after the incident, was later apprehended at his mother’s home, Orlando Mayor Buddy Dyer and Police Chief Val Demmings told reporters.
“There is one confirmed fatality,” Demmings said. Local media had earlier reported two people killed in the shooting.
The shooting, coming a day after a mass shooting at a U.S. army base in Texas which killed 13 people, caused panic in and around the Orlando office building as armed police moved in and evacuated workers.
Orlando police said the 40-year-old suspect was a former employee at the office of an engineering and architecture company in the building who had returned to the location and started firing.