Sixteen deaths in Karachi on Saturday showed that the target killings that reared their heads in the city in the past few months are by no means over. The continued violence on Sunday claimed 26 more lives. The countrys largest city, also its only port and financial and industrial hub, has been afflicted by these politically motivated killings for years. At times, these killings die down, but crop up again. As they have now. Gang warfare between criminals has been often blamed, but the political background shared by almost all the victims makes it quite evident that the motivation is political. This has vitiated the atmosphere of the city, and has made it difficult to do business there. The recent killings are particularly painful not only because they are large in number, but also they came on the eve of a by-election; that reflect badly upon the coalition government. Indeed, the Lyari pair killed on Saturday not only consisted of workers of the party heading the provincial coalition, but also heading the central. When workers of all parties, not just those heading a coalition, are being killed, the lives of ordinary citizens will also be on the line. It is incumbent upon the ruling coalition, both at the Centre and in Sindh, to address the underlying causes of tension in the coalition, rather than undertake merely cosmetic measures.