The National Accountability Bureau (NAB) has formed a joint investigation team (JIT) to probe the assets case against Pakistan Peoples Party (PPP) leader Khursheed Shah. Khursheed has been accused of financial irregularities of worth Rs1.4 billion, NAB sources said. As many as 18 people, including Khursheed, have been named in the reference. The NAB has also nominated two wives of the PPP stalwart, his two sons, Nisar Mughal, Saqib Awan and others in the reference. Earlier, the anti- corruption agency while asking the national institutions to provide officers expert in white collar crime said that the JIT investigation is necessary before filing reference against the PPP leader.