, ▁s inking ▁several ▁tro op ▁b arg es ▁and ▁inf lic ting ▁heavy ▁cas ual ties . ▁Fort ▁Dr um ▁surrender ed ▁to ▁Japanese ▁forces ▁following ▁the ▁fall ▁of ▁Cor reg idor ▁on ▁ 6 ▁May ▁ 1 9 4 2 , ▁and ▁was ▁subsequently ▁occupied ▁by ▁them ▁until ▁ 1 9 4 5 . ▁The ▁ 2 0 - ft ▁thick ▁rein for ced ▁concrete ▁roof ▁enabled ▁Fort ▁Dr um ▁to ▁with stand ▁the ▁concentr ated ▁and ▁frequent ▁p ounding ▁it ▁received ▁from ▁the ▁Japanese ▁from ▁about ▁ 1 5 ▁February ▁to ▁ 6 ▁May ▁ 1 9 4 2 . ▁No ▁U . S . ▁personnel ▁in ▁Fort ▁Dr um ▁were ▁killed ▁during ▁the ▁sie ge ▁and ▁only ▁five ▁were ▁injured . ▁The ▁four ▁ 1 4 - inch ▁tur ret ▁guns ▁were ▁never ▁out ▁of ▁action ▁and ▁were ▁still ▁firing ▁effectively ▁five ▁minutes ▁before ▁the ▁fall ▁of ▁Cor reg idor . ▁As ▁at ▁the ▁other ▁for ts ▁in ▁the ▁Philippines , ▁Fort ▁Dr um ' s ▁g arrison ▁executed ▁destruction ▁procedures ▁on ▁the ▁guns ▁prior ▁to ▁the ▁Japanese ▁arriv ing ▁to ▁secure ▁the ▁fort ; ▁this ▁is ▁why ▁one ▁ 1 4 - inch ▁gun ▁has ▁fallen ▁back ▁inside ▁its ▁tur ret . ▁The ▁surrender ▁of ▁the ▁Man ila ▁Bay ▁for ts ▁marked ▁the ▁end ▁of ▁U . S . ▁resistance ▁in ▁the ▁Philippines . ▁ ▁Philippines ▁Camp aign ▁( 1 9 4 4 – 1 9 4 5 ) ▁ ▁In ▁ 1 9 4 5 ▁following ▁the