A U.S. senator has raised the possibility of privacy violations by Google and Apple’s three dimensional map rendering technologies.

US Senator Charles Schumer expressed his concerns in letters to Google and Apple, saying that the two companies’ high-resolution 3D mapping technologies can catch minor but private activities in areas like backyards. He also called their use of reconnaissance planes and high-resolution technology a “peeping Tom technology”.

In response, Google said that although its 3D images are not that clear, it is internally reviewing the concern surrounding its mapping service. Apple responded by promising to delete images containing faces and personal information like drivers’ licenses.

Google and Apple are planning to announce new 3D mapping services this month. They say that the 3D technology will provide far clearer images than satellite images.