The blast happened on Saturday morning at The Fountains shopping centre in Plantation, west of Fort Lauderdale in Broward County.
Dramatic pictures show the devastation caused by the explosion.
One witness told US television station WPLG: “There was a huge flash of light … it lit up the whole sky and it was loud … this surpassed fireworks … your ears were ringing. It just looks like an apocalypse.”
Concerned residents took to social media following the explosion.
One tweeted: “I live a mile at most from today’s gas explosion in Plantation. Heard the bomb-like sound. Felt my house shake. Multiple injuries being reported. Praying nobody was killed, and that no one you know was nearby and affected.”
Another shared: “That explosion shook my entire house. I live a mile away & my fan shook so hard I thought it was going to fall.”
Plantation fire and police departments said on Twitter that the street was closed to traffic.
The fire department called it a gas explosion adding that there were “multiple patients”.
Police tweeted: “Avoid the area of University Drive and Peter’s Road. Fire and PD are working an incident involving an explosion. Command post is set up on S. University Drive in the 800 block. Media Command post set up north of this location.
“All stores and businesses in the area of the Fountains Plaza and the Plantation Marketplace plaza near LA Fitness will be shut down until futher notice until Fire Personnel can determine that it is safe to return. Please do not come into this area if possible.”
This is a breaking story. More to follow.