A manhunt is under way to find British hostage and father-of-two Alan Henning, 47 (left at a refugee camp), who was seized while working at a Syrian aid camp and paraded in ISIS’ latest terror video (right). Unmanned drones were sent to target militants as RAF Tornados remained on 12-hour standby, with the Prime Minister condemning the ‘monsters’ who beheaded Mr Henning’s fellow aid worker David Haines (inset). A chilling video uploaded by militants showed the 44-year-old reciting a scripted rant against Britain and David Cameron personally.