"A Philippine Navy personnel sustained severe injury after the CCG's (China Coast Guard's) intentional high-speed ramming during the rotation and resupply mission to the BRP Sierra Madre (LS57) on June 17," a military statement said.

The shoal, which hosts a tiny Philippine garrison stationed on a deliberately beached old warship, has been a focus of escalating confrontations between Chinese and Philippine ships in recent months as Beijing steps up efforts to push its claims to the disputed area.

Shortly after the incident, the Chinese coast guard reported that a Philippine resupply ship in the area had "ignored many solemn warnings from the Chinese side".

It "approached the... Chinese vessel in an unprofessional way, resulting in a collision", Beijing said, accusing the ship of having "illegally broken into the sea near Ren'ai Reef".

"The Chinese Coast Guard took control measures against the Philippine ship in accordance with the law," it added.

But the Philippine armed forces called China's version of events "misleading", decrying "the illegal presence and actions of Chinese vessels within the Philippines' exclusive economic zone".

Manila's national task force on the West Philippine Sea later said the Chinese vessels had "engaged in dangerous manoeuvres, including ramming and towing".

"Their actions put at risk the lives of our personnel and damaged our boats," it said.

In an update, the Philippine military on Tuesday made its first casualty report from the incident, adding that the injured navy personnel "has been safely evacuated and received prompt medical treatment".

It gave no details on the sailor's injury and also did not comment on news reports that a sailor had lost a finger and that Chinese personnel also boarded a Philippine vessel and seized several guns and inflatable boats.

The Second Thomas Shoal lies about 200 kilometres (120 miles) from the western Philippine island of Palawan and more than 1,000 kilometres from China's nearest major landmass, Hainan island.

Beijing claims almost the entirety of the South China Sea, brushing aside competing claims from several Southeast Asian nations including the Philippines and an international ruling that its stance has no legal basis.

It deploys coast guard and other boats to patrol the waters and has turned several reefs into militarised artificial islands.

It has in recent months stepped up moves against Philippine vessels in the area around Second Thomas Shoal.

This month, Manila accused Chinese boats of illegally seizing food and medicine airdropped to the Philippine outpost in the area.

It was the first time supplies had been seized, the military said.

Chinese personnel on the boats later dumped the items in the water, Philippine Navy spokesman for the West Philippine Sea Commodore Roy Vincent Trinidad said.

It was not clear if they belonged to the Chinese coast guard or navy, the military said.

China in response insisted the Sierra Madre was illegally grounded on the reef and urged the Philippines to "stop making trouble".