The officials would not identify the C.I.A . officers who were the subjects of the investigation , but said that some were now serving at a senior level within the C.I.A . They said that those who faced potential charges included at least one former C.I.A . station chief in Lima , Peru 's capital , at least one former chief of the aviation mission assigned to a base in Peru , and at least one official who had been based at C.I.A . headquarters in Langley , Va. .