Rangers conducted a targeted operation near Teen Talwar, Clifton area and arrested some suspects including a key culprit of Ms Shahid’s murder case.
Rangers spokesperson said the arrested killer Kaleem was also involved in several murder cases.
Law enforcement agencies have already three suspects in this connection.
PTI leader Imran Ismail said killers of Zahra Shahid should be arrested forthwith.
He said PTI was striving to bring back lost peace in Karachi .
Ms Shahid was fatally shot outside her residence in Karachi’s Defence Housing Authority Phase-IV in May last year in an attempted robbery incident. However, later PTI chief Imran Khan blamed the MQM for its involvement in the killing.
MQM denied the claim, saying PTI was politicizing the issue.