Updated

The FBI investigation of state Sen. Ron Calderon involves legislation he introduced for a Los Angeles-area water district that uses his brother as a consultant.

The FBI raided the Democrat's Sacramento offices Tuesday but hasn't said why.

On Wednesday, two people told The Associated Press they were questioned by the FBI about Calderon and his brother, Tom.

Michael Franchek, former vice president of EcoGreen Services, says agents contacted him twice to discuss Tom Calderon's work for the Central Basin Municipal Water District.

And a Los Angeles-area elected official says agents asked him about legislation written by Ron Calderon for Central Basin. The official spoke on condition of anonymity because the investigation is ongoing.