U.S. Bancorp's U.S. Bank unit has become one of Los Angeles’s biggest slumlords by letting hundreds of foreclosed homes fall into disrepair, city officials said in a court filing, Bloomberg News reported today. In the past four years, the bank has become the owner of more than 1,500 residential properties in the city that it acquired title to as the trustee for mortgages that were held in mortgage-backed securities, the city attorney said in a civil law enforcement action filed yesterday in California state court in Los Angeles. The city accused the bank of violating California’s unfair competition law and the Los Angeles municipal code. It seeks $2,500 a day for each violation.