After nearly two days of closed-session meetings, the board for the Los Angeles Unified School District placed Superintendent Alberto Carvalho on paid administrative leave amid a federal investigation into his time as the head of Miami's school district.On Friday, the board announced that they made the decision unanimously. The board appointed its chief of operations, Andres Chait, as interim superintendent.Carvalho began his newest contract with LAUSD two weeks ago. It was a four-year, $1.7 million deal. On Wednesday, the FBI served a series of search warrants at Carvalho's home and the Los Angeles Unified School District's headquarters, officials said. Sources told CBS News that the FBI also raided a Florida residence linked to Carvalho. The reason for the warrants is unknown after the FBI confirmed that the underlying affidavit remained under seal.Law enforcement sources told CBS News that the investigations in both states are directly related to Carvalho.…