China sends documents to the United Nations backing claim to Paracel Islands . Vietnam also claims the region and is angry about alleged incursion into its territory . Tensions increased after China sent an oil tanker into disputed waters . Both sides have accused the other of damaging their ships .
China sends documents to the United Nations backing claim to Paracel Islands . Vietnam also claims the region and is angry about alleged incursion into its territory . Tensions flared after China sent an oil rig into disputed waters . Both sides have accused the other of ramming their ships .