Dozens missing.

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The number of people missing in the Surfside, Florida, building collapse rose to 159, with four confirmed dead, as hundreds of search-and-rescuers worked through Friday. Rescuers have found no new survivors since Thursday.

With the most accessible victims already pulled from the rubble, efforts now are largely focused on "void spaces," protected pockets formed by large objects like refrigerators or sofas that might have created a place where someone could be trapped without being crushed, The Washington Post reports.

"It's devastation. It's still being called search and rescue," said state senator Jason Pizzo, who noted that hope is nevertheless dimming for families and friends even as authorities have remained cautiously optimistic about finding more survivors. But "I know they're not going to find them [alive]," Jeanne Ugarte, whose close friends were visiting family at the tower, told The Associated Press. "It's been too long."