FOUR British aid workers who were kidnapped by gunmen in Liberia along with two other westerners returned home on Wednesday, vowing to continue their work in the world’s hot spots. After a reunion with family and friends as they flew in to London’s Heathrow airport, the four held a press conference to speak of their three-day ordeal. The four were seized a week ago at Kolahun, in the north west of the west African country, which is home to many refugees from Sierra Leone and the base of western non-governmental charity organisations.