At least four police forces in Britain are now investigating allegations of historical sexual abuse against the late former prime minister Edward Heath.<br /><br /> Detectives in Jersey, Kent and London are involved. <br /><br /> On Tuesday police in Wiltshire in southwestern England appealed for witnesses who might be able to substantiate allegations against the former politician. <br /><br /> Heath died in 2005 at the age of 89.<br /><br /> A British MP, Tom Watson, said that the Metropolitan Police in London had been investigating one allegation for over a year. <br /><br /> The Guardian newspaper claims a fifth force, Hampshire is also looking at claims.