The PML-N faced defeat in NA-249 by-polls due to internal differences within the party over the name of the candidate for the electoral contest in Karachi, sources told ARY News.
Ismail sought seeking details of the voting process from the Election Commission of Pakistan (ECP) and asked the commission to scrutinise the thumb expressions of voters.
The election officials served notices to PTI members of Sindh Assembly Firdous Shamim Naqvi, Saeed Afridi, Bilal Ghaffar, Raja Azhar, Shahnawaz Jadoon and Shahzad Awan to leave the constituency.
The NA-249 seat was relinquished by the PTI's Faisal Vawda, who had won the seat in the 2018 general election, beating PML-N’s Shehbaz Sharif by a small margin of 723 votes.
The party's head Syed Mustafa Kamal, Syed Hafeezuddin and Humayun Usman have received nomination papers for the by election, scheduled to take place on April 29.