The B-1B Lancer could be used to strike North Korean missile sites - here's what the bomber can do

The US Air Force conducted an exercise near the Korean Peninsula on Thursday involving two B-1B bombers and Japanese and South Korean fighter jets.

"The bilateral continuous bomber presence (CBP) mission was planned in advance ... and was not in response to any current event," the Air Force said in a statement.

North Korea called it a "surprise" strike drill - and they might not be incorrect.

The Pentagon has actually devised a plan to take out the North's missile sites just in case President Donald Trump ever orders the preemptive strike, and the B-1B Lancers would a play a key role.

Here's what we know about the plan and about what the Lancer can do.