Dear you need to understand the dynamics of Karachi has changed since 90s era, now MQM is not the sole responsible of unrest in KARACHI....and every violence which take place in KARACHI is not a political violence
Karachi is facing three type of violence
1- Political Violence: In this political violence PPP, MQM,ANP, JSQM, SUFP are involved
2- Religious/ Sectarian Violence: Lasker/ Jaish of both sects are involve in it.....with the help of some political leaders.
3- Local Gangsters: they are involved in Land Grabbing, Parchi, extortion and Kidnapping they seek refuge in political parties having strong hold in their area of operations.
So the only solution for KARACHI problem is to Depoliticize and Deweaponize whole city for some time at least for 5 years.