Eleven people were killed in Karachi on Thursday as the death toll rose to over 40 this week with rival political parties fighting it out on the city streets while law enforcement agencies looked on helplessly.
The Muttahida Qaumi Movement (MQM), which broke its political alliance with the ruling Pakistan Peoples Party last week, claimed that the killings were being carried out against its workers who were being targeted by militants of rival parties.
Dr Farooq Sattar of the MQM accused president Asif Ali Zardari of "looking the other way" as MQM activists were killed.
Opposition leader Nawaz Sharif has called for a report on the killings and said that the breakdown of law and order in Karachi.
He said that the government was "so engrossed in corruption" that it had little time for maintaining peace in Pakistan's largest city.
Streets in certain areas of Karachi were deserted as shops remained closed and armed men roamed in different areas.