North Korea fires 2 missiles after second US submarine arrives in South Korea

North Korea fired two short-range ballistic missiles into the sea off its east coast Monday, following the arrival of a U.S. nuclear-powered submarine in South Korea earlier in the day.

The development comes amid heightened tensions between Washington and Pyongyang. The submarine that arrived Monday is the second major U.S. vessel deployed to South Korea, following one docked last week that is capable of firing nuclear ballistic missiles.

South Korea’s Joint Chiefs of Staff said the latest missiles were fired consecutively just before midnight from near North Korea’s capital. Both missiles, according to the joint chiefs, traveled about 248 miles before landing in the waters off the eastern coast of the Korean Peninsula.

South Korea’s military condemned the launches as a “grave provocation” threatening regional peace and stability. It said U.S. and South Korean intelligence officials were analyzing the launches and were working together to tighten monitoring of North Korean military moves.  

North Korea’s apparent act of retaliation is the third round of weapons testing since last week. Pyongyang responded to the arrival of the nuclear-capable U.S. submarine in South Korea last week — the first such docking in decades — by firing test ballistic missiles and cruise missiles. 

The North Korean defense minister also issued a threat saying the docking of the nuclear-capable submarine could be grounds for North Korea to use nuclear weapons. 

Earlier Monday, the U.N. Command said it has begun conversations with North Korea about U.S. Army Pvt. Travis King, who crossed the border into North Korea last week and was subsequently detained. U.S. officials have expressed concern for his well-being, but U.N. officials have declined to say what they know about his condition.

The Associated Press contributed reporting.