This week saw a dramatic escalation of tensions on the Korean Peninsula. As North Korea promised to engulf the U.S. territory of Guam in "enveloping fire", President Trump tweeted that the U.S. military is "locked and loaded" should North Korea "act unwisely".
The North's missile and nuclear programs have been shrouded in secrecy for years, but recent tests have shed more light on their capabilities. Here is what's currently known.
North Korean missiles can reach the continental United States.