U.S. officials have warned Google and Apple of privacy concerns as the companies fly 'military-grade spy planes' over cities to gather data for 3D map services. Staffers for Senator Charles Schumer, a Democrat from New York, met with Google executives on Monday to discuss privacy issues related to the camera-equipped planes. They plan to meet with Apple on Friday. The senator's office also plans to reach out to Microsoft and other companies that may be developing similar technologies. Senator Schumer said he wanted to make sure the companies 'understand the significance of our concerns over the potential publication of images captured in people's backyards and other private settings.' The lawmaker wrote to the rival Silicon Valley corporations on Monday accusing them of 'an unprecedented invasion of privacy' by using technology capable of imaging objects as small as 4in Source: The Coming Crisis