China's increasingly powerful navy has denied firing on a Vietnamese boat in disputed waters in the South China Sea, state media said Wednesday, as its craft made wide-ranging patrols of the region.

The denial came during naval patrols which Tuesday took Chinese ships within 80 kilometres (50 miles) of the Malaysian coast, amid rising international tensions over the disputed sea.

The navy described a Vietnamese claim that Chinese vessels had fired on one of its fishing boats as "sheer fabrication", Xinhua news agency reported.

Vietnam's foreign ministry said Monday a fishing boat was "chased and shot at by a Chinese vessel" and had its cabin set ablaze. Hanoi called the incident a "serious violation" of its sovereignty.

"There is no such things that Chinese vessel fired with weapons or the Vietnamese boats caught fire," Xinhua quoted a Chinese naval official as saying, adding that the Chinese vessel had fired "two warning signal shells".

Xinhua said four Chinese naval ships are currently patrolling around the Spratly Islands, a collection of islets and reefs which are also wholly or partly claimed by Vietnam, the Philippines, Taiwan, Malaysia and Brunei.

It said the ships Tuesday had reached the James Shoal, a collection of submerged rocks 80 kilometres off Malaysia and about 1,800 kilometres from the Chinese mainland.

The shoal marks the extreme limit of China's claims in the region, which it bases on a map published in the 1940s.

Ships in the patrol include the Jinggangshan, China's largest amphibious landing ship, Xinhua said.

Vietnam demands fishing boat compensation
Hanoi, Vietnam (UPI) Mar 27, 2013 - Vietnam is seeking compensation for damages to a fishing boat after it was hit by fire from a Chinese patrol vessel off the disputed Paracel Islands.

A formal complaint was lodged with the Chinese Embassy in Hanoi over the March 20 incident after a patrol boat chased the fishing boat before firing on it.

A Vietnamese Foreign Ministry spokesman said the attack was "an extremely serious incident," a report by the official Vietnamese News Agency said.

Spokesman Luong Thanh Nghi said China violated Vietnam's sovereignty over the Hoang Sa archipelago -- the Vietnamese name for the Paracels -- threatened the lives of Vietnamese fishermen and damaged their property.

"Vietnam strongly protests, urging China to investigate and seriously deal with the wrongful and inhumane act and compensate Vietnamese fishermen for their loss."

The incident is the latest clash between Vietnam and China involving the Paracels, a dispute that spilled over into a brief armed conflict between South Vietnam and China in 1974.

Prior to the conflict Vietnam and China claimed various of the unoccupied rocky islands -- known as the Xisha Islands by Beijing -- which lie about 180 nautical miles from both Vietnam and China's Hainan Island.

An attempted landing by Vietnamese soldiers on a Chinese-claimed island resulted in a 2-day battle, including warships, that left China in complete control of the more than 30 islets, sandbanks and reefs covering around 5,800 square miles of ocean.

Beijing claims sea rights over a swath of area extending south as far as the island of Borneo.

The Paracel Islands issue is one among many South China Sea disputes involving China and regional neighbors, including the Philippines and Japan.

In January, China said it will survey the disputed Diaoyu Islands to "safeguard China's marine rights," a Foreign Ministry spokesman said at the time.

The survey of the islands -- known as the Senkaku Islands by Japan which administers them -- will be part of a larger project of island and reef mapping started in 2009, spokesman Hong Lei said in a report by state-run Xinhua news agency.

"Diaoyu Island and its affiliated islets have been the inherent territory of China since ancient times," said Hong.

Beijing and Manila have been at diplomatic loggerheads over competing claims for the Scarborough Shoal, a triangular collection of reefs covering less than 60 square miles and whose highest point is around 10 feet above sea level.

The Philippines-administered shoal is more than 400 miles off the Chinese coast but 150 miles off the coast of Zambales, a province on the western shore of Luzon Island, the largest and most northern Philippines island.

Since mid 2012 Chinese patrol boats have been sailing in waters around the shoal, at times blocking entrances to passages among the islets.