Philippine and Chinese vessels collided near the Second Thomas Shoal in the South China Sea on Monday, the China Coast Guard (CCG) said, as Beijing steps up efforts to push its claims over the disputed area.

Known in Chinese as the Ren'ai Reef, the Second Thomas Shoal has seen an escalating number of confrontations between Chinese and Philippine ships in recent months.

These have often taken place during Philippine attempts to supply a garrison of Philippine troops on a grounded navy vessel, the Sierra Madre, aimed at asserting Manila's claims to the reef.