There are more questions than answers after a 12-story building collapsed in Surfside, Florida, on Thursday.
Local officials appeared to have few ideas about what may have caused wings of the 136-unit building to inexplicably crumble.
Scientists, however, have long noted the risk of building on the shifting sands of a barrier island like Miami Beach, especially with rising sea levels. That may not be the reason for this collapse, but it remains an engineering challenge in the region.
For more on this story, go to NBC News.