Vietnam's coast guard has released a video it says shows one of its vessels being deliberately rammed by a Chinese patrol craft near the disputed Paracel Islands. It comes on the same day that Beijing reiterated its right to drill for oil in the region of the South China Sea also claimed by Hanoi.
Ships from the two countries have been in a standoff near the islands, located about 160 miles east of Vietnam, since Sunday. China is attempting to deploy an oil rig there.
The video appears to support Hanoi's claims that the Chinese are acting aggressively to force Vietnam ships from the scene of the oil and gas operation. It shows a ship with Chinese markings overtaking another vessel and then slamming into its stern quarter.
A Chinese foreign ministry official in Beijing said it was the Vietnamese patrol ship that purposely hit the other vessel. China says it has "maintained a lot of restraint" in the face of "intensive provocations" by Vietnam, according to The Associated Press.
"He said the drilling operation was taking place in Chinese territory and Beijing had acted with the utmost restraint.
"Vietnam rushed vessels to the area off its central coast after Beijing announced it was sending a drill ship to prospect for oil on 1 May.
"Vietnam has plans for oil exploration of its own in the region, which it claims falls under Vietnamese sovereignty."
The AP reports that Vietnam's main stock market index "recorded its biggest one-day drop since 2001 on fears of a protracted stalemate or possible conflict between the neighboring nations, which have fought two naval skirmishes in the waters since 1974 and have history of conflict going back 1,000 years."