(Las Vegas, NV)  –  Police have stepped up their investigation of an alleged extortion plot against a county commissioner.  The “Review-Journal” reports search warrants were served yesterday at the home of Commissioner Steve Sisolak’s former girlfriend, Kathleen Vermillion.  Sisolak claims Vermillion tried to shake him down for nearly four-million dollars.  Vermillion sued Sisolak amid allegations she misused money from a children’s charity.  The former Henderson councilwoman has stepped down from the charity.