MQM and their rivals (ANP etc) have been involved in murdering police officials, no doubt about this. Whether it was in reaction, it is debatable. However, killing police officials comes under mutiny.
However, MQM does not seem to have any connection with this particular incidence, and now that TTP (alias JI/JUI) scum has claimed the responsibility, this bickering should come to and end. Both MQM and TTP (alias JI/JUI) are involved in anti-state activities, both are terrorist organizations, and both are a threat. However, at this point of time, TTP (alias JI/JUI) appears to be a more imminent threat, hence it should be dealt first, while keep MQM on check during all this while. Shahid Hayat is a brave and able police officer. He should request the GoP to somehow get Dr. Shoaib Suddal no-board, as an advisor or something. Karachi operation can be conducted more effectively with Dr. Suddal as an advisor.