“Over 80 MDFR units including #TRT (Technical Rescue Teams) are on scene with assistance from municipal fire departments,” Miami Dade Fire Rescue said in a tweet.
Surfside Mayor Charles W Burkett confirmed to CNN’s Leyla Santiago that there is at least one fatality.
“This is a horrific catastrophe. In the United States, buildings just don’t fall down,” Mr Burkett said.
The mayor told reporters that ten people were treated on scene and that the building has been cleared.
The mayor went on to say that the building was undergoing roof work, but he couldn’t say whether that was a contributing factor to the collapse.
Footage from the ground showed fire crews pulling a survivor, a teen boy from the rubble.
The collapse sent a cloud of debris through the neighborhood, coating cars up to two blocks away with a light layer of dust.
Miami Dade Fire Rescue is conducting search and rescue. Authorities have not revealed how many people live in the building, but some witnesses in the exclusion zone say they fear friends or loved ones are still inside.
Kimberly Morales told CNN she lives in the building across the street from the collapse and was awakened by building alarms going off and pounding on her door.
“I woke everyone up in the room because when I looked out the window, I saw everyone outside,” she told CNN.
“I told everyone to hurry up and leave the building.”
Police blocked nearby roads, and scores of fire and rescue vehicles, ambulances and police cars swarmed the area.
“We’re on the scene so it’s still very active,” said Sgt Marian Cruz of Surfside Police Department.
“What I can tell you is the building is twelve floors. The entire back side of the building has collapsed.”
Photos and video from the scene show that the collapse affected half the tower. Piles of rubble and debris surrounded the area just outside the building.
The department has yet to say what may have caused the collapse near 88th Street and Collins Avenue.
“I have never seen so many ambulances and police in my life all at once,” a man who lives nearby told CNN.
“It looked like something from 9/11, literally.
“The entire building collapsed from the 14th floor.
“So there’s a third of the entire building, that you cannot see from the street, but it’s completely gone.
“It almost looks like 9/11 or if a bomb hit or something.
“It just completely wiped it out. There’s a pile of rubble.”
Survivors and those from surrounding buildings have been evacuated to a nearby community centre as crews work to find anyone else alive.
According to the Miami Herald, the 12-storey condo tower, part of Champlain Towers, is an oceanside condo built in 1981 with more than 100 units.
The area is a mix of new and old apartments, houses, condominiums and hotels, with restaurants and stores serving an international combination of residents and tourists.
The community provides a stark contrast from bustle and glitz of South Beach with a slower paced neighbourhood feel.