Western experts monitor China's nuclear sites for signs of damage
China's main centers for designing, making and storing nuclear arms lie in the shattered earthquake zone, leading Western experts to look for signs of any damage that might allow radioactivity to escape. A senior federal official, who spoke on the condition of anonymity because of the delicacy of the issue, said the United States was using spy satellites and other means to try to monitor the sprawling nuclear plants. "There appear to be no immediate concerns," the official said.