Threat of sleeper cells in US has 'never been higher': CBP

USA TODAY - For more and to sign up click here Tara Suter The threat of sleeper cells in the U.S. has “never been higher," though there are no current specific threats, according to U.S. Customs and Border Protection (CBP). A memo sent Saturday from CBP Commissioner Rodney Scott, obtained by The Hill’s sister network NewsNation, said "thousands of Iranian nationals have been documented entering the United States…