Karachi is the largest city, main seaport and the financial heart of Pakistan, as well as the capital of the province of Sindh.
The city has an estimated population of 18 to 20 million, making it the most populous city in the country, one of the world's largest in terms of population and also the 10th largest urban agglomeration in the world.
It is Pakistan's premier centre of banking, industry, economic activity and trade and home to Pakistan's largest corporations, the stock exchange, central bank and naval base.
In addition Karachi is one of the Pakistan's most dangerous cities as far as human life is concerned.
Crimes common to most big cities, organized gangs of extortionists, land grabbers, mercenaries in turf wars among political parties, ethnic groups and criminal gangs alleged to be linked to and protected by political parties have complicated the city's law and order woes.
For decades, Karachi has held a place of unenviable prominence in Pakistan in terms of sectarian, political and ethnic strife that has grown increasingly violent in recent years.