Members of a military detachment move around aboard the BRP Sierra Madre, run aground on the disputed Second Thomas Shoal, part of the Spratly Islands, in the South China Sea March 29, 2014. According to local media, two Chinese Coast Guard vessels on Saturday tried to block a Philippine government civilian ship from bringing troops and supplies to the military detachment. BRP Sierra Madre has been aground on the disputed shoal, which is known as the Ren'ai reef in China and the Ayungin Shoal in the Philippines, since 1999. REUTERS/Erik De Castro (PHILIPPINES - Tags: POLITICS MARITIME MILITARY)