Officials say 17 people were killed in a shooting at a high school in south Florida.
The suspected shooter - a 19-year-old man - has been taken into custody.
The Broward Sheriff's Office initially responded to reports of an active gunman in the city of Parkland.
In a statement on social media, police initially said there were reports of 'multiple victims'.
Sheriff Scott Israel later confirmed that 17 people had died.
"I'm saddened to say that 17 people lost their lives."- Sheriff Scott Israel #stonemanshooting
— Broward Sheriff (@browardsheriff) February 14, 2018
Local schools superintendent Robert Runchie had earlier confirmed to reporters there were numerous fatalities, in what he described as an 'horrific situation'.
Footage from local media showed students being evacuated from Stoneman Douglas High, with deputies surrounding the building.
Today, close to Marjory Stoneman Douglas High School’s dismissal, students and staff heard what sounded like gunfire. The school immediately went on lockdown but is now dismissing students. We are receiving reports of possible multiple injuries. Law enforcement is on site.
— Broward Schools (@browardschools) February 14, 2018
President Trump said his 'prayers and condolences' were with the families of the victims.
My prayers and condolences to the families of the victims of the terrible Florida shooting. No child, teacher or anyone else should ever feel unsafe in an American school.
— Donald J. Trump (@realDonaldTrump) February 14, 2018