US aircraft carrier arrives in S Korean waters

A nuclear-powered U.S. aircraft carrier and its battle group began exercises with South Korean warships on Monday, hours after North Korea fired two short-range ballistic missiles in an apparent protest of the allies’ expanding drills.

The seventh missile test this month underscored heightening tensions in the region as both the North’s weapons tests and the U.S.-South Korea joint military exercises have intensified in a cycle of tit-for-tat.The launches may have been timed for the arrival of the USS Nimitz and its strike group, including a guided missile cruiser and two destroyers, which engaged in air defense exercises and other drills with South Korean warships in waters near Jeju Island.