The death toll in last week’s condominium-building collapse in Surfside, Fla., rose to 12, officials said Tuesday evening, with 149 people still unaccounted for, as President Biden planned to visit the site and a prosecutor said she will ask a grand jury to examine the disaster.

Miami-Dade State Attorney Katherine Fernandez Rundle said Tuesday she would ask the grand jury to determine “what steps we can take to safeguard our residents without jeopardizing any scientific, public safety, or potential criminal investigations.”

Grand juries in Florida are able to examine criminal matters and explore issues of public policy, returning indictments as well as reports aimed at recommending changes to lawmakers.

Here are some significant developments

  • A Washington Post examination of video and images, as well as interviews with structural engineers, a key witness and an investigator, deepens questions about the potential role of damage to a deck in the pool area.
  • Months before the collapse, the president of the building’s condominium association sent a letter warning that damage to the structure’s concrete support system was “accelerating” and “would begin to multiply exponentially” without millions of dollars in repairs.
  • The building’s finances were also strained ahead of a construction project that the association president said “the building needs so badly,” documents obtained by The Washington Post show.
  • The veteran engineer hired by Surfside to investigate the collapse began his on-site inspection Tuesday, focusing on whether the building’s still-standing portion is at risk of falling down.
  • Search-and-rescue efforts at disaster sites such as Champlain Towers South pose wicked challenges.