▁the ▁mess enger ▁was ▁unable ▁to ▁reach ▁the ▁British ▁position . ▁On ▁ 2 1 ▁April , ▁the ▁advanced ▁guard , ▁number ing ▁ 7 3 3 ▁and ▁compr ising ▁a ▁det achment ▁of ▁the ▁ 3 1 st , ▁two ▁companies ▁of ▁the ▁ 7 8 th , ▁one ▁of ▁the ▁ 3 5 th , ▁and ▁De ▁Roll ' s ▁Regiment , ▁with ▁a ▁pic quet ▁of ▁drag o ons , ▁was ▁surrounded . ▁▁ ▁the ▁surv iv ors , ▁who ▁had ▁exp ended ▁all ▁their ▁am mun ition , ▁became ▁prisoners ▁of ▁war . ▁General ▁Stewart ▁reg ained ▁Alexand ria ▁with ▁the ▁remainder ▁of ▁his ▁force , ▁having ▁lost ▁over ▁ 9 0 0 ▁men , ▁killed , ▁wounded ▁and ▁missing . ▁H undred s ▁of ▁British ▁heads ▁were ▁exposed ▁on ▁st akes ▁in ▁C airo , ▁and ▁the ▁prisoners ▁were ▁march ed ▁between ▁these ▁m util ated ▁remains . ▁However , ▁this ▁time ▁the ▁British ▁prisoners ▁were ▁well ▁treated , ▁and ▁officers ▁were ▁given ▁qu arters ▁in ▁the ▁Cit adel . ▁ ▁Sie ge ▁of ▁Alexand ria ▁The ▁defeat ▁at ▁Ros etta ▁forced ▁Mack en zie - F ras er ▁to ▁re cons ider ▁his ▁position , ▁and ▁British ▁troops ▁were ▁ordered ▁to ▁re occup y ▁Alexand ria ▁which ▁was ▁soon ▁bes ie ged ▁by ▁the ▁Arab ▁and ▁M aml uk ▁troops ▁from ▁C airo . ▁Using ▁his ▁fe igned ▁good ▁will ▁as ▁a ▁pre text , ▁Muhammad ▁Ali ▁then ▁offered ▁the ▁British ▁the ▁freedom ▁to ▁receive ▁supplies ▁from