▁by ▁law ▁enfor cement ▁and ▁intelligence ▁ag encies , ▁but ▁their ▁use ▁has ▁raised ▁significant ▁civil ▁liberty ▁and ▁priv acy ▁concerns ▁and ▁is ▁strictly ▁reg ulated ▁in ▁some ▁countries . ▁ ▁In ▁March ▁ 2 0 2 0 , ▁British ▁daily ▁The ▁Guardian , ▁based ▁on ▁the ▁claims ▁of ▁a ▁wh ist leb lower , ▁accused ▁the ▁government ▁of ▁Sa udi ▁Arab ia ▁of ▁explo iting ▁global ▁mobile ▁tele com ▁network ▁weak ness es ▁to ▁sp y ▁on ▁its ▁citizens ▁travel ing ▁around ▁the ▁United ▁States . ▁The ▁data ▁shared ▁by ▁the ▁wh ist leb lower ▁in ▁support ▁of ▁the ▁claims , ▁showed ▁that ▁a ▁system atic ▁sp ying ▁campaign ▁was ▁being ▁run ▁by ▁the ▁kingdom ▁explo iting ▁the ▁fla ws ▁of ▁SS 7 , ▁a ▁global ▁mess aging ▁system . ▁The ▁data ▁showed ▁that ▁millions ▁of ▁secret ▁tracking ▁commands ▁origin ated ▁from ▁Sa udi ▁in ▁a ▁duration ▁of ▁four - month s , ▁starting ▁from ▁November ▁ 2 0 1 9 . ▁ ▁R F ID ▁tag ging ▁ ▁Radio ▁Fre quency ▁Ident ification ▁( R F ID ) ▁tag ging ▁is ▁the ▁use ▁of ▁very ▁small ▁electronic ▁devices ▁( called ▁" R F ID ▁tags ") ▁which ▁are ▁applied ▁to ▁or ▁incorpor ated ▁into ▁a ▁product , ▁animal , ▁or ▁person ▁for ▁the ▁purpose ▁of ▁identification ▁and ▁tracking ▁using ▁radio ▁waves . ▁The ▁tags ▁can ▁be ▁read ▁from ▁several ▁meters ▁away . ▁They ▁are ▁extremely ▁in exp ensive , ▁cost ing ▁a ▁few ▁c ents ▁per ▁piece , ▁so ▁they ▁can