A tanker carrying Iranian oil by the country’s top oil shipping firm was ablaze and spewing cargo into the East China Sea on Sunday after colliding with a Chinese freight ship, leaving the tanker’s 32 crew members missing. The Sanchi, run by the country’s top oil shipping operator, collided with the CF Crystal about 160 nautical miles off the coast near Shanghai and the mouth of the Yangtze River Delta on Saturday evening, the Chinese Ministry of Transportation said in a statement. It was not immediately clear how much environmental damage had been caused or the volume of oil spilled into the sea.