The new contingent of Filipino marines replaced troops at the Second Thomas Shoal, where the arrival last month of Chinese ships sparked diplomatic protests from the Philippines.
Defense Secretary Voltaire Gazmin said that the shoal lies within the Philippines’ internationally recognized 200-nautical mile (370-kilometer) exclusive economic zone. China claims almost the entire South China Sea as its own and last year took control of another shoal in the Philippines’ economic zone, prompting Manila to seek U.N. arbitration.


