A Russian sailor died and two others were being treated for suspected poisoning on Wednesday following a toxic leak inside a tanker just off Istanbul, local authorities said. Officials were alerted to the emergency aboard the Panama-flagged tanker "Swanlake" at 5:30 pm when the vessel was several miles from Istanbul's Asian coastline, the governor's office said in a statement . "The incident is believed to have been caused by a leak in the vessel's cold tank. One crew member died and two others