There is no intelligence pointing to a specific plot, but the U.S. has shared this information with executives at domestic and international carriers.
The Transportation Security Administration says that people traveling to the U.S. from overseas may experience additional screening at airports.
Placing explosives and explosive components inside humans is not a new idea. But a U.S. security official says there is new intelligence pointing to a fresh interest in using this tactic.
The official spoke on condition of anonymity to discuss sensitive security information.