Vietnamese and Chinese relations strained even further Tuesday when a Chinese vessel opened fire on a Vietnamese fishing boat in an area of the South China Sea.

The Vietnamese government did not specify whether or not anyone sustained injuries, but did say the situation was "very serious." They have filed a formal complaint with the Chinese embassy in Hanoi.

The oil and fishing-rich, largely uninhabited area called the Paracel Islands has been the center of a dispute between the two countries for a while; both entities claim the location their own.

The fishing boat was passing through the islands when an unmarked Chinese vessel chased it down and shot a flare, the Vietnamese government wrote in an official statement released Tuesday.

They have demanded China pay for necessary repairs on the damaged boat.

"Vietnam strongly protests, urging China to investigate and seriously deal with the wrongful and inhumane act, and compensate Vietnamese fishermen for their loss," Vietnamese Foreign Ministry spokesman Luong Thanh Nghi told the BBC.

China responded by saying their actions were "necessary and legitimate."

"A Vietnamese shipping boat...entered China's waters for illegal activity," Hong Lei, Chinese Foreign Ministry spokesperson, said. "No damage was caused to the fishing boat from Vietnam at the time."

This is not the first time Asian countries have squared-off on this portion of the South China Sea-The Philippines, Taiwan, Malaysia and Brunei also assert this location belongs to them.

Tensions have steadily heightened as each country tightens up their respective authoritarian stances, NPR recently blogged, which has led to "[frequent] standoffs at sea."

In 2012, the Philippines and China fought at great length over another contested area nearby by the name of the Scarborough shoal.

Earlier this month, Chinese surveillance ships pushed two Vietnamese fishing boats out of disputed waters, in a situation very similar to yesterday's.