The U.S. Air Force appears to have deployed two B-1B bombers to Guam amid signs that a seventh nuclear test by North Korea is imminent. 

According to the aviation tracker Aircraft Spots on Wednesday, two B-1Bs departed Ellsworth Air Force Base in South Dakota and arrived at Andersen Air Force Base in Guam around 7 a.m. Tuesday coordinated universal time.

The tracker said this was the start of a "new Bomber Task Force deployment amid heightening tensions with North Korea."

The deployment of B-1Bs to Guam is seen as the U.S. sending a strong warning to North Korea, which has reportedly completed preparations for its seventh nuclear test.

The B-1B is one of the U.S.' three strategic bombers, alongside the B-52 and B-2, and it can reach the Korean Peninsula from Guam in two hours.