A white pickup truck was lined up with other floats at the Stonewall Pride Parade & Street Festival in Wilton Manors on Saturday evening when the driver reportedly hit the gas pedal and ran over two bystanders, WPLG reported.
Trantalis said he believes the crash was "deliberate" and an attack against the LGBTQ community.
"As reports come in and more details unfold, we send love to our #LGBTQ family and all those impacted by the events that took place today at the #Pride event in #WiltonManors-including our #PFLAG chapter members", they tweeted.
Our thoughts and prayers are with those affected by the unfortunate accident that occurred when the Stonewall Pride Parade was just getting started.
Rep. Debbie Wasserman Schultz (D-Fla.), who was present at the parade and sitting in a convertible, was nearly hit by the vehicle.
Some witnesses said the crash appeared to be an intentional act, but Fort Lauderdale Police Detective Ali Adamson told reporters that authorities were investigating all possibilities. The annual event draws about 35,000 to the city, which lies north of Fort Lauderdale.
One of the victims later died from their injuries, Mr Trantalis said, and WPLG-TV reported the driver of the truck was taken into custody. She said the other man was expected to survive. The FBI is assisting with the investigation.
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Uefa said a crisis meeting had taken place with both teams and match officials and further information will be communicated. Eriksen was given urgent medical attention on the field for about 10 minutes before he was carried off on a stretcher.
She tweeted Saturday night, "I am deeply shaken and devastated that a life was lost".
"We were at the start of the parade, right in front of Fort Lauderdale High School", spectator Christina Currie, who was there with her husband and their two elementary school aged children, told the Sun-Sentinel, Fort Lauderdale's local newspaper. "May the memory of the life lost be for a blessing", she added.
She said: "All of a sudden there was a loud revving of a truck and a crash through a fence".
The parade has been put on hold and police are on the scene, NBC affiliate WTVJ reports.
"This tragedy took place within feet of me and my BSO team, and we are devastated having witnessed this horrific incident", said the statement from Broward County Sheriff Gregory Tony.
"Though authorities are still gathering information, we know two individuals marching to celebrate inclusion and equality were struck by a vehicle".
June is Pride Month, which commemorates the 1969 Stonewall riots sparked by repeated police raids on a popular gay bar in NY.