The Dawn quoted the officials, as saying, that 15 people were dead and 15 others were rescued.
However, the different officials said around 50-100 passengers were on board.
Deputy Commissioner (DC) Thatta Nasir Baig, confirming the death toll said, "15-20 people were rescued and admitted to the hospital in an unconscious state."
Rescue operation is still underway in coordination between Navy and Army units in the area, Commissioner Hyderabad Division Dr Saeed Magnejo said.
Most of the passengers are residents of Karachi, he added. (ANI)