0 0   a . m . ▁on ▁Th urs day , ▁April ▁ 9 , ▁the ▁c ask ets ▁were ▁carried ▁to ▁three ▁he ars es , ▁and ▁a ▁process ion ▁of ▁an ▁estimated ▁ 1 , 0 0 0 ▁police ▁vehicles ▁travel led , ▁along ▁with ▁the ▁Pitts burgh ▁Fire fig h ters ▁Memorial ; ▁Cleveland ▁Police ▁and ▁Pitts burgh ▁Police ▁De pt . ▁P ipes ▁and ▁Dr ums ; ▁Pitts burgh ▁Fire ▁De pt . ▁P ipes ▁and ▁Dr ums ; ▁NY PD ▁Emer ald ▁Society ▁P ipes ▁and ▁Dr ums ; ▁Philadelphia ▁Police ▁and ▁Fire ▁P ipes ▁and ▁Dr ums ; ▁Cam den ▁County ▁N J ▁Emer ald ▁Society ▁P ipes ▁and ▁Dr ums ; ▁Union ▁County ▁N J ▁P ipes ▁and ▁Dr ums ; ▁Washington ▁D . C . ▁Regional ▁P ipes ▁and ▁Dr ums ; ▁Cleveland ▁P ipes ▁and ▁Dr ums ; ▁Atlantic ▁County ▁( N J ) ▁P ipes ▁and ▁Dr ums ; ▁and ▁many ▁more ▁ ▁pipe ▁bands , ▁from ▁the ▁City - Count y ▁Building ▁along ▁the ▁Martin ▁Luther ▁King ▁Jr . ▁East ▁Bus way ▁to ▁the ▁University ▁of ▁Pitts burgh ' s ▁Peters en ▁Events ▁Center . ▁H undred s ▁of ▁officers ▁had ▁been ▁standing ▁at ▁attention ▁outside ▁the ▁center ▁for ▁nearly ▁two ▁hours . ▁Gu ests ▁at ▁the ▁ceremony ▁included ▁F BI ▁Director ▁Robert ▁Mu eller ; ▁Al leg hen y ▁County ▁District ▁Att orney ▁Steven ▁Z app ala ; ▁county ▁executive ▁Dan ▁On or ato ; ▁Pennsylvania ▁Governor ▁Ed ▁R end