Pakistani Islamic terrorists are fleeing to Karachi, a major port and the largest city in Pakistan. This is seen as an indicator that many terrorists are going to be quiet for a while. That would be welcome to most Pakistanis. In the last year, there has been a sharp increase in Islamic terrorist bombing in Pakistan, but nearly all of them have taken place in the tribal territories (in the west and northwest, along the Afghan border). Nearly all the terrorists are Pushtun tribesmen, or al Qaeda foreigners (from Arab nations, Central Asia or Chechnya). In the last five months, the Pakistani armed forces has gone to war, with over 100,000 troops converging on the tribal territories, and killing thousands of Taliban gunmen, and scattering the terrorist militias that, earlier in the year, considered themselves invulnerable. Taliban safe houses and weapons storage sites have been captured, and police and soldiers are going door to door looking for senior Taliban members. Naturally, one would expect most Taliban to flee for the hills, especially for distant kin, and a place to wait out the Winter, and, hopefully, the army offensive.
But hundreds of Taliban have fled to Karachi. That's because the city is home to over two million Pushtuns (out of a city population of 12 million). About half these Pushtuns are Afghans (refugees from the 1980s war with Russia) and their children. Since Pushtuns, as a group, are ill equipped for urban living (low literacy, and few technical skills), most are poor. The low rent neighborhoods are full of Pushtuns, who are also overrepresented in criminal gangs. But the Pushtuns are closely watched by the police, and have earned some peace by not encouraging or supporting terrorists. Whenever this understanding is violated, as it is from time to time, the police lock a lot of people up, and even expel Afghans from the country. This last threat is much feared, and there's really no way to protect yourself from it, other than having done the cops some favors in the counter-terrorism department.
So the fleeing Taliban can expect shelter in Karachi, but not a new base from which to plan and carry out more terrorist attacks. This has always been a great fear among non-tribal Pakistanis (80 percent of the population). The non-tribal majority in Karachi, even those who are Islamic conservatives, will turn in suspicious Pushtuns quickly if they suspect terrorism. The recent flood of cell phone service into the city has made that much easier, and the terrorists know it. The police also know that the Taliban are in Karachi, and are out looking for them. But as long as these beaten Taliban keep their heads down, they will be hard to find.