KARACHI (Reuters) - Pakistani police have arrested a surgeon who is accused of stealing a kidney from a patient during an operation to remove a gall bladder, police said on Saturday.Mohammad Kashif complained to police that he went in for the gall bladder operation on May 7 and ended up minus one kidney.Police arrested the surgeon on Friday in the southern city of Karachi."We are investigating the matter as we are keen to know why the doctor removed the kidney and where it has gone," senior police officer Zubair Mehmood told Reuters