CROWN POINT, Ind. (WLS) -- The FBI and Indiana State Police raided the offices of Lake County Sheriff John Buncich Thursday morning.Investigators entered the offices of the Lake County Government Center in Crown Point Thursday morning and left later with several boxes of documents.Indiana State police said they assisted the FBI on executing the search warrant. An FBI spokesperson declined to comment on the nature of the investigation.The Times of Northwest Indiana reports that federal agents and state police entered the building with dollies. Dean Delisle told the newspaper he was in an office where police records are kept seeking a copy of an accident report when investigators entered and ordered everybody including employees to leave the building. He says investigators began "taking pictures of everything."State and federal investigators' cars also were parked outside Buncich's home in Crown Point.A spokesman for Buncich says his department is cooperating with the FBI.