Four U.S. F-22 stealth fighters are flying over South Korea amid growing tensions following North Korea's rocket launch, AP reported.
The high-tech planes capable of sneaking past radar undetected were seen flying near a U.S. air base near Seoul on Wednesday.
Pyongyang will likely view the arrivals of the planes as a threat as they are a clear show of force against the country.
The United States often sends powerful and sophisticated warplanes to South Korea in times of tension with North Korea.