Travelers flying into the United States from certain overseas airports will be required to turn on their cellphones and other electronic devices for the preflight scanning and inspection, the Transport Security Administration (TSA) announced yesterday (July 6). People with a unpowered device will not be allowed to board their flights, the TSA said in an online posting, and those passengers may also undergo additional screening. The increased security measure is a response to new intelligence about possible terrorist plots, a DHS official told CNN, adding that the affected airports are mostly located in the Middle East and Europe.