PML(N) President Nawaz Sharif has expressed serious concern over the situation in Karachi, especially in Lyari, and held that government has totally failed to control law and order in that parts.  While talking to PML(N) General Secretary, Sindh, Saleem Zia and Ifranullah Marwat at Raiwind on Wednesday, Nawaz Sharif said tension gripped the whole nation owing to situation in Karachi where killing and crime had become order of the day.