Surfside, United States: Questions mounted on Monday about how a residential building in the Miami area could have collapsed so quickly and violently last week, as the death toll rose to 10 with more than 150 still unaccounted for, and desperate families feared the worst. Experts are looking at possible pre-existing critical flaws in the structure of the apartment tower in Surfside, near Miami Beach, which pancaked into a pile of smoking rubble in the early hours of Thursday.