The fighter jet, from the Chinese military's Southern Theater Command, crashed in an open area in the southern island province of Hainan, the navy said in a statement on social media.

The southern command oversees some of the country's most sensitive areas including the South China Sea, where there has been a spate of violent clashes between Chinese and Philippine vessels in recent years around disputed reefs and islands in the area.

"The pilot successfully ejected, and no collateral damage was caused on the ground," the statement said.

An investigation into the cause of the crash has been launched and the navy is organising efforts to handle the aftermath, it added.

China has for years sought to expand its presence in contested areas of the sea, brushing aside an international ruling that its claim to most of the waterway has no legal basis.

In recent months, Beijing has more firmly asserted its territorial claims in the South China Sea, where countries such as Vietnam, Indonesia, and the Philippines are defending their own claims.

Last month, the Philippine Coast Guard condemned "dangerous" manoeuvres by a Chinese Navy helicopter it said had flown within metres of a surveillance flight carrying a group of journalists over the contested Scarborough Shoal.