Pickpockets have been spotted in the Thames Valley and police are warning people to be on their guard. The light-fingered thieves are targeting people who put their mobile phone into the back pocket of their trousers. Police say that pickpockets generally work in teams, sometimes distracting their victim while an accomplice removes items and then blends into a crowd. Thefts can take just seconds to carry out. Risks can also be minimised by not hanging items, such as bags, on the back of a chair or pushchair. Belongings on the floor should not be placed out of sight. Those carrying large quanti…