MULTAN,April 2nd:Pakistan Seraiki Party (PSP)on Friday observed black day and staged a demonstration against non-induction of a clause regarding constitution of seraikistan province in the 18th constitutional amendment. They also burnt an effigy of Raza Rabbani chairman of constitutional committee.The demo was led by Barrister Taj Muhammad Khan Langah chief of PSP.He told newsmen that Pakistan Seraiki Party would observe black day on March 31st every year against 18th constitutional amendment.He said that today Balochs, Sindhis, Punjabis and Pushtoons were celebrating the day while we are mourning today because we were neglected.He said that slavery would be tightened in Punjab with the provincial autonomy and Punjabi bureaucracy would suck our blood.He held Mian Nawaz Sharif ,Syed Yousaf Raza Gilani and Asif Ali Zardari for neglecting the demand of 50 million people of Seraikistan.