Authorities have said Brian Williams, a top deputy to Mayor Karen Bass, is suspected of sending an anonymous threat about a bomb inside City Hall in October.

Los Angeles Deputy Mayor Brian K. Williams (left), who oversees public safety departments, is under federal investigation for his alleged connection to a City Hall bomb threat, prompting his immediate administrative leave.

Officials say FBI agents searched the home of a Los Angeles deputy mayor this week as part of an investigation into whether he made a bomb threat against City Hall.