Cabarrus County in North Carolina lost $1,728,082.60 after sending $2.5 million to scammers pretending to be contractors building their new high school. BEC scams are scams where crooks deceive employees of privately-held companies and public organizations into wiring money to entities they trust but whose bank accounts were changed to ones controlled by the criminals. Banks could only recover $776,518.40 of the $2,504,601 that remained in traceable accounts.
Source: https://www.bleepingcomputer.com/news/security/north-carolina-county-lost-17-million-in-bec-scam/