At least one person died Thursday after a wing of the Champlain Towers South, a 40-year-old, 12-story residential building, collapsed in the Surfside area of Miami Beach.
Firefighters have been working since early morning to rescue people who were trapped in the rubble.
Hotels already had opened to some displaced residents, the county's mayor said, and deliveries of food, medicine and more were being hastily arranged.
Many relatives and close friends have gathered in the vicinity of the building, outside the security line, or have moved to nearby health centers such as the Aventura Hospital and Jackson Memorial, to look for their relatives and loved ones.
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Residents who do not require medical attention have been transferred to the Surfside Community Center at 9301 Collins Avenue and 93rd Street.
They will remain there until they are reunited with their family members.
Authorities have also set up a phone number for people looking for information about the residents of the Champlain Towers building. That number is 305-614-1819.
Miami-Dade Fire Rescue is asking those who live at the Champlain Towers South to fill out a Wellness Check Form in an effort to locate all tenants.
The building has 136 apartments and MDFR estimates that about 55 of them were affected by the collapse. It is not known how many were occupied or how many people were inside during the collapse, but it is believed that there are many who do not live there permanently.
The Miami-Dade County Technical Rescue Team is working on the scene with the help of fire departments from several Miami- Dade and Broward municipalities.