The death toll from the building collapse in Surfside, Florida, U.S., has climbed to 18 after six more bodies were retrieved, local authorities announced on Wednesday.

A total of 147 people remained missing and were feared trapped in the ruins of the Champlain Towers South condo, said Miami-Dade County Mayor Daniella Levine Cava at a news conference.

Two of the 18 confirmed fatalities were children, aged 10 and 4, according to the mayor.

President Joe Biden and his wife, Jill Biden, planned to visit the scene of the incident on Thursday.