ISLAMABAD - President Dr Arif Alvi and Prime Minister Shehbaz Sharif on Friday expressed grief over the loss of lives in a traffic accident near Sehwan Sharif in Sindh. In their separate messages, the president and the prime minister extended their condolences to the families of the deceased. At least 18 people drowned as a passenger bus fell into a floodwater ditch near Sehwan district on Thursday.